Change: use TCP for everything except for master-server and initial server scan (#9130)

This means that pressing Refresh button and adding servers manually
now uses TCP.

The master-server and initial scan are still UDP as they will be
replaced by Game Coordinator; no need to change this now.

If we query a server that is too old, show a proper warning to the
user informing him the server is too old.

Add: admin menu for companies in multiplayer games

You can now easily do:
- a password reset (unlock)
- remove an empty company (reset company)

Feature: rework in-game Online Players GUI

The GUI now more clearly shows some basic information about the
server you joined, your client name (and the ability to change it),
and what players are in which company.

It also contains useful buttons to press to join companies, chat
with other people, and for admins to kick/ban people.

Additionally, renamed "advertised" to "visibility"; this has to
do with future additions, but also because it is more clear in
wording.

Remove: "language" field from server/client

The original idea was that people could find a server they could
talk in their native language on. This isn't really used in that
way. There are several reasons for removing this:

- the client also sends his "language" to the server, but nothing
is doing anything with this.
- flags are a bad way to represent languages, and over the years
we had several (rightfully) complaints about this.
- most servers have their language set to "All", and prefix the
servername with the language it is about. This is a much more
efficient way to do the same.

All in all, this feature should go back to the drawing board.
Maybe it could work in another form, but this form is not it.

Feature: allow a toggle to enable/disable vsync

Vsync should be off by default, as for most players it will be
better to play without vsync. Exception exist, mainly people who
play in fullscreen mode.

Change: scale heightmaps we export to highest peak and inform the user of this value

Before this commit, it scaled to map-height-limit. Recently this
could also be set to "auto", meaning players don't really know
or care about this value.

This also means that if a player exported a heightmap and wanted
to import it again, looking like the exact same map, he did not
know what value for "highest peak" to use.

Feature: allow setting a custom terrain type to define highest peak

At least, TGP will try to reach it. It heavily depends on the map
if it is reachable at all. But for sure it will do its atmost to
get there!

Add: allow setting the highest mountain for heightmaps

It will add some slack to the map height limit if that was set
to auto.

Feature: auto-detect map height limit based on generated map

This opens up the true power of the TGP terrain generator, as it
is no longer constrainted by an arbitrary low map height limit,
especially for extreme terrain types.

In other words: on a 1kx1k map with "Alpinist" terrain type, the
map is now really hilly with default settings.

People can still manually limit the map height if they so wish,
and after the terrain generation the limit is stored in the
savegame as if the user set it.

Cheats still allow you to change this value.

Change: rename setting "max_heightlevel" to "map_height_limit"

This better reflects what it is, and hopefully removes a bit of
the confusion people are having what this setting actually does.

Additionally, update the text on the setting to better inform
users what it is doing exactly, so they can make an educated
decision on how to change it.

Next commit will introduce an "auto" value, which should be the
new default. The rename has as added benefit that everyone will
start out on the "auto" value.

Change: remove "maximum map height" from the New Game GUI

This setting influence the max heightlevel, and not as the name
suggests: the height of the generated map.

How ever you slice it, it is a very weird place to add this
setting, and it is better off being only in the settings menu.

Commits following this commit also make it more useful, so users
no longer have to care about it.

Feature: setting to indicate desert coverage for tropic climate

This is an indication value; the game tries to get as close as it
can, but due to the complex tropic rules, that is unlikely to be
exact.

In the end, it picks a height-level to base the desert/tropic
line on. This is strictly seen not needed, as we can convert any
tile to either. But it is the simplest way to get started with
this without redoing all related functions.

Feature: setting to indicate snow coverage for arctic climate (replaces snow line height)

Setting the snow coverage (in % of the map) makes a lot more sense
to the human, while still allowing the niche player to set (by
finding the correct %) a snow line height they like. This makes for
easier defaults, as it decoupled terrain height from amount of snow.

Maps can never be 100% snow, as we do not have sprites for coastal
tiles.

Internally, this calculates the best snow line height to approach
this coverage as close as possible.

Fix: if bootstrap failed, it could end with an empty screen instead of error

There are various of ways bootstrap can fail:
- Failing network connection
- Incomplete download
- No write permissions
- Disk full
- (others I forgot)

They all result in a screen with no windows. To ensure we at least
always show something when anything bad happens, if the bootstrap
is not successful, show a screen what the next step for the human
should be.

Codechange: remove special strings for language and resolutions (#8824)

As OpenTTD grew, we found other ways to do this, and we are no
longer in need for a hack like this.

Add: Option to (dis-)allow accelerated video drivers. (#8819)

The video drivers using the OpenGL backend are currently our only
accelerated drivers. The options defaults to off for macOS builds and
to on everywhere else.

Co-authored-by: Michael Lutz <michi@icosahedron.de>

Add: Malaysia Ringgit as Currency

Cause why not

*Update the formating

Add: settings to limit your fast-forward game speed

By default this setting is set to 2500% normal game speed.

Add: Indonesia Rupiah as in-game currency (#8616)

The exchange rate is actually more like 19,000, but OpenTTD
doesn't handle such high exchange rates kindly.

Change: remove warning in cheat window and reduce it to a note (#8538)

Although meant as a funny joke towards the player, our social
standards have changed since 2004, and such "jokes" are no
longer acceptable by the community as a whole.

The only value of the message is that people are informed the
information is stored in the savegame. This is mostly useful for
us, developers, as some of those cheats can have side-effects
which people report.

While at it, styled the GUI a bit better, as the way the text
was presented was odd.

Fix #7972: show invalid orders to stations that don't accept your vehicle (#8516)

Before it was shown as a normal order, but the vehicle was skipping
it. This was rather unclear to the user. Now it is red and contains
text with some hints what is going on.

The text is prefixed rather than post-fixed, as we have many
post-fixes already.

Change: move "give money" from client-list to company window

This is a much better location for this button, as you send
money from one company to another company, not from player
to player.

This is based on work done by JGRPP in:
https://github.com/JGRennison/OpenTTD-patches/commit/f82054339124cc6b89c5f4f9dac2d9da62f0108b
and surrounding commits, which took the work from estys:
https://www.tt-forums.net/viewtopic.php?p=1183311#p1183311

We did modify it to fix several bugs and clean up the code while
here anyway.

The callback was removed, as it meant a modified client could
prevent anyone from seeing money was transfered. The message
is now generated in the command itself, making that impossible.

Change: [Linkgraph] Pause the game when linkgraph jobs lag (#6470)

Check if the job is still running two date fract ticks before it is due
to join, and if so pause the game until its done.
When loading a game, check if the game would block immediately due to
a job which is scheduled to be joined within two date fract ticks,
and if so pause the game until its done.
This avoids the main thread being blocked on a thread join, which appears
to the user as if the game is unresponsive, as the UI does not repaint
and cannot be interacted with.
Show if pause is due to link graph job in status bar, update network
messages.
This does not apply for network clients.

Fix: next 67 savegame versions are used in PatchPacks; skip them (#8411)

Various of PatchPacks (Spring 2013, Joker, ChillPP) used versions
slightly higher than ours. Of course, as time went by, this
caught up with us, and we are now almost pushing a new version
that would conflict with them. To avoid users creating unneeded
issues about "why can I not load my savegame", lets be ahead of
the curve and flat-out refuse to load them.

Version-wise, this is totally fine. We have ~32k versions to go
before we run out (0x8000 is masked by JGRPP; we should avoid
using that). At the rate we bump savegames, this is not going to
happen in any sane reality.

Feature: Option to group vehicle lists by shared orders

This applies to all kinds of vehicle lists, as well as the "vehicle groups" window.

Fix: prefix the Nth vehicle with "#" when ungrouped

This is for consistency; most other objects add a # to indicate
it is the Nth of that object, except for Trains / RVs / Ships /
Aircrafts.
This becomes painfully apparent with unnamed vehicles in groups,
which do get a "#".

Feature: Show group name as part of the default vehicle name.

Only if the vehicle is member of a group and does not have a user defined name.

Codechange: Spell 'Viewport' consistently

Some places in the codebase misspell 'Viewport' as 'ViewPort' or 'view_port'.
This patch makes everything consistent.

Add: INR currency (#8136)

Co-authored-by: ilayarja97 <ilayarja97@gmail.com>

Feature #7756: Allow server to supply a reason to kicked/banned clients

This commit adds the missing feature of allowing the server owner to
provide a reason for kicking/banning a client, which the client sees in
a pop-up window after being kicked. The implementation extends the
network protocol by adding a new network action called
NETWORK_ACTION_KICKED that is capable of having an error string, unlike
the other network error packages. Additionally, the kick function
broadcasts a message to all clients about the kicked client and the
reason for the kick.

Feature: Configurable game ending year

Functionally reverts 683b65ee1

Add: Scale oil refinery edge distance up by map size

Also scales oil rig distance up, since they use the same algorithm.

Add #6887: Option to show zone inside local authority boundary of towns

Can be found at town information > local authority window
Layout for button is same as Graph Keys
Turn on/off for every town individually

Change: Limit memory allocations for each Squirrel instance

This can avoid out-of-memory situations due to single scripts using up the entire address space.
Instead, scripts that go above the maximum are killed.
The maximum is default 1 GB per script, but can be configured by a setting.

Remove: ENABLE_NETWORK switch

This switch has been a pain for years. Often disabling broke
compilation, as no developer compiles OpenTTD without, neither do
any of our official binaries.

Additionaly, it has grown so hugely in our codebase, that it
clearly shows that the current solution was a poor one. 350+
instances of "#ifdef ENABLE_NETWORK" were in the code, of which
only ~30 in the networking code itself. The rest were all around
the code to do the right thing, from GUI to NewGRF.

A more proper solution would be to stub all the functions, and
make sure the rest of the code can simply assume network is
available. This was also partially done, and most variables were
correct if networking was disabled. Despite that, often the #ifdefs
were still used.

With the recent removal of DOS, there is also no platform anymore
which we support where networking isn't working out-of-the-box.

All in all, it is time to remove the ENABLE_NETWORK switch. No
replacement is planned, but if you feel we really need this option,
we welcome any Pull Request which implements this in a way that
doesn't crawl through the code like this diff shows we used to.