Remove: logically dead code from font cache

The outer if statement checks for 'aa' being false, so within the inner
statements anything checking aa will have a known result and the other
branch from there will be dead code.

Fix 11ab3c4: [NewGRF] Overflow when determining cargo mask for string code 9A 1E

9A 1E: Print unsigned word as name of a cargo type (translated for GRF version >= 7).

Codechange: split settings.ini over several files (#9421)

This reduced the load on compilers, as currently for example MacOS
doesn't like the huge settings-tables.

Additionally, nobody can find settings, as the list is massive and
unordered. By splitting it, it becomes a little bit more sensible.

Update: Translations from eints
spanish (mexican): 44 changes by absay
italian: 2 changes by CoderLel

Update: Translations from eints
spanish (mexican): 54 changes by absay

Fix: reduce the amount of debug messages on -dsl=2 (#9420)

LoadCheck makes it sound like something is really broken while
loading savegames, while it really is perfectly normal, as most
chunks do not implement LoadCheck.

Fix 9e32c618: network revision was always empty (#9419)

Shadowing the variable you intend to write in tends to do that ;)

Update: Translations from eints
spanish (mexican): 6 changes by absay

Update: Translations from eints
portuguese (brazilian): 1 change by Vimerum

Update: Translations from eints
hindi: 26 changes by ritwikraghav14

Update: Translations from eints
catalan: 1 change by J0anJosep

Codechange: Add CMake source group for the saveload compat tables.

While at it, fix the not-working OpenGL sub-group.

Update: Translations from eints
norwegian (bokmal): 1 change by Anolitt
japanese: 1 change by scabtert

Codechange: make savegame-version checks more obvious in SlCompanyLiveries::Load

num_liveries indirectly contained the same information, but this
makes reading these things pretty difficult. So use IsSavegameVersionBefore()
like everywhere else instead.

Codechange: using "until" in function names can be confusing

IsSavegameVersionUntil() did a [0, N] check, not [0, N) as the
name suggests.

Until can be a confusing word, where people consider it to be
including the upperbound. Dictionary states it means "before",
excluding the upperbound. There are long debates about who is right.

So, simply remove away from this ambiguity, and call it "before"
and "before or at". This makes the world easier for everyone.

Cleanup: remove SLE_NULL and friends

We no longer need them. If you want to remove a field .. just
remove it! Because of the headers in the savegame, on loading,
it will do the right thing and skip the field.

Do remember to bump the savegame version, as otherwise older
clients can still load the game, but will reset the field you
have removed .. that might be unintentially.

Add: store headers for most savegame chunks

When a header is added, the chunk changes from CH_ARRAY type to
CH_TABLE type.

Feature: framework to make savegames self-descriptive

We won't be able to make it fully self-descriptive (looking at you
MAP-chunks), but anything else can. With this framework, we can
add headers for each chunk explaining how each chunk looks like
in detail.

They also will all be tables, making it a lot easier to read in
external tooling, and opening the way to consider a database
(like SQLite) to use as savegame format.

Lastly, with the headers in the savegame, you can freely add
fields without needing a savegame version bump; older versions
of OpenTTD will simply ignore the new field. This also means
we can remove all the SLE_CONDNULL, as they are irrelevant.

The next few commits will start using this framework.

Update: Translations from eints
english (us): 1 change by 2TallTyler
german: 1 change by Wuzzy2
dutch: 1 change by Afoklala

Change: move sensitive information to secrets.cfg and private information to private.cfg

We often ask people for their openttd.cfg, which now includes their
passwords, usernames, etc. It is easy for people to overlook this,
unwillingly sharing information they shouldn't.

By splitting this information over either private.cfg or secrets.cfg,
we make it more obvious they shouldn't be sharing those files, and
hint to what is inside them.

Codechange: simplify SaveVersionInConfig()

Clearly someone really wanted to generalize the function, but
in reality it makes it a lot longer than needed. Let's keep it
simple.

Codechange: C++-ify the usage of IniFile in settings.cpp

Instead of creating the object on heap and use a pointer, create
the object on stack and use a guaranteed-not-null pointer.
The size of IniFile doesn't warrent the forcing to heap.

Additionally, use a subclass instead of a function to do some
initial bookkeeping on an IniFile meant to read a configuration.

Codechange: move network-related settings out of settings.ini

This to prepare the code to split up network-related settings
into private / secrets / generic.

Codechange: use a contructor for NewsItem to set the values

And use std::unique_ptr to manage the memory of the allocated data

Update: Translations from eints
finnish: 1 change by hpiirai

Change: [strgen] Change warnings for translations into infos (#9406)

Unless invoked with -w, --warning ("print a warning for any untranslated strings") or -t, --todo ("replace any untranslated strings with '<TODO>'").

Eints normally fixes the warnings after a Pull Request, so it is not really useful information for the developer to see as a warning.

Update: Translations from eints
swedish: 27 changes by joeax910
korean: 4 changes by telk5093
russian: 1 change by Ln-Wolf
portuguese: 1 change by azulcosta

Update: Translations from eints
swedish: 1 change by joeax910

Update: Translations from eints
swedish: 6 changes by joeax910
finnish: 1 change by hpiirai
catalan: 9 changes by J0anJosep

Update: Translations from eints
swedish: 1 change by joeax910

Fix #9386: compilers failing to compile with LTO by using variants instead of new + unique_ptr

With std::variant all memory can be figured out at compile time, so the compiler needs to keep track of fewer elements. It also saves out a unique_ptr and its memory management, over a slight impact for resolving a setting.

Codechange: use C-style strings instread of std::string in the SettingDesc constructor

This as using std::string causes much more variables to be tracked, potentially causing problemes for certain compilers in certain situations

Codechange: instead of "naked" initializer lists, declare the type in the saveload macros

This to help variant's constructor to be able to resolve the constructor of the setting

Codechange: remove overloading on UpdateServiceInterval

One UpdateServiceInterval has two parameters to update the service interval for a vehicle type, the other for all vehicle types at once. Rename the latter to help with function resolution for the introduction of variants.

Codechange: [Network] Remove overload on NetworkValidateClientName

Rename the zero-parameter NetworkValidateClientName to NetworkValidateOurClientName to make it clearer it is performed on our client name, and to make it a non-overloaded function to aid with the variant being added a few commits later

Change: prevent palette updates during copying to the video driver

ThreadSanitizer rightfully notices that the game-thread could
update the palette while the draw-thread is copying it for local
use. The odds of this are very small, but nevertheless, it does
carry a very good point.

It wouldn't hurt the application in any way, but it might cause
visual glitches on the screen.

Codechange: use _cur_palette the same in all the drivers

It was a bit of a mixed bag. With this change, gfx.cpp is in
control who accesses _cur_palette from the video-drivers.

Update: Translations from eints
swedish: 1 change by joeax910
dutch: 9 changes by Afoklala

Codechange: [OSX] Use more exact enum names where introduced with the 10.12 SDK.

The enum values still have the exact same numerical values, but the 10.12
SDK introduced more explicit names (e.g. like NSEventTypeApplicationDefined
instead of NSApplicationDefined) for several enum constants.
Use them when available.

Update: Translations from eints
english (us): 9 changes by 2TallTyler

Update: Translations from eints
swedish: 1 change by kustridaren
korean: 1 change by telk5093

Update: Translations from eints
swedish: 12 changes by joeax910

Fix: Wrong cargo line position in IndustryCargo window. (#9383)

Resolved by changing calculation to determine the offset based on centring the cargo lines in the available space.

Fix: don't propagate shift/ctrl state till next game-tick (#9381)

When the game-loop is very slow, it was easily possible to start
the loop with _shift_pressed being false, but end with
_shift_pressed being true. This doesn't hurt the game as such,
but for the user this can be very weird: I pressed "Buy Vehicle",
pressed shift a bit later, and I still get a cost indication.

Fix: on startup, NewGRF scan could case race-condition (#9382)

Creating a thread was not thread-safe. The irony.

The video-driver has a function GameLoopPause() which first checks
if the thread is the game-thread or not. For this it needs access
to this->game_thread. This variable is set in StartNewThread().

However, due to timing, it is well possible GameLoopPause() is
called from the thread well before this->game_thread is assigned.

And so we have a race-condition!

Simply solve this by preventing a thread to start till we are
done with our bookkeeping.

Fix: thread safety issue during exiting the game (#9380)

_exit_game is read by the draw-thread to know when to exit, but
most of the time written by the game-thread.

Update: Translations from eints
spanish: 3 changes by MontyMontana
hindi: 28 changes by ritwikraghav14

Codechange: mark chunks that are not stored as CH_READONLY

This makes it easier to spot chunks that have a save_proc that
is a nullptr, but also prevents confusion, where it looks like
the CH_ type of a chunk has influence on how it is being read.
It is not, it is only used for saving.

Change: rework GLOG chunk to be more like the rest

Basically it is very similar to Vehicles, where there first is
a type field, followed by data of that type. So this commit makes
it looks like how Vehicles solved that.
This removes a lot of custom "keeping track of length" stuff.

Change: rework several CH_RIFF chunks to use CH_ARRAY instead

This adds two byte extra to those chunks, and might feel a bit
silly at first. But in later changes we will prefix CH_ARRAY with
a table header, and then this change shines.

Without this, we could still add headers to these chunks, but any
external reader wouldn't know if the CH_RIFF has them or not. This
way is much more practical, as they are now more like any other
chunk.

Codechange: add the ability to save/load a std::vector

std::vector<bool> is not possible, as .. that is a nice special
case in C++.

This new type will be used in next commit.

Change: prefix SL_ARR with the length of the array

This means that during loading we can validate that what is saved
is also that what is expected. Additionally, this makes all list
types similar to how they are stored on disk:
First a gamma to indicate length, followed by the data.
The size still depends on the type.

Codechange: make it more obvious SlArray supports SLE_VAR_NULL

In the end, the code was already doing the right thing, but a few
functions deep, and not really obvious. When validating what objects
can handle SLE_VAR_NULL, it is nicer to just have this obvious.

Codechange: use SL_NULL if you want to store null-bytes or load to nothing

Using SL_ARR for this gives us a bit of trouble later on, where we
add a length-field to SL_ARR. This of course is not the intention
of SLE_CONDNULL. So better seperate it.

Change: switch SL_DEQUE and SL_REFLIST length field to a gamma

The current SaveLoad is a bit inconsistent how long a length field
is. Sometimes it is a 32bit, sometimes a gamma. Make it consistent
across the board by making them all gammas.