Codechange: Use vehicle tile hash to build depot vehicle list. (#12186)

This avoids iterating the entire vehicle pool.

Codechange: Build station and depot vehicle lists from shared order lists. (#11676)

The brings some performance advantages:

* No need to iterate all vehicles and check for primary vehicle as only vehicles that can have orders are listed.
* Shared orders only need to be tested once instead of for each vehicle sharing them.
* Vehicle tests only need to be performed on the first shared vehicle instead of all.

Codechange: automatic adding of _t to (u)int types, and WChar to char32_t

for i in `find src -type f|grep -v 3rdparty/fmt|grep -v 3rdparty/catch2|grep -v 3rdparty/opengl|grep -v stdafx.h`; do sed 's/uint16& /uint16 \&/g;s/int8\([ >*),;[]\)/int8_t\1/g;s/int16\([ >*),;[]\)/int16_t\1/g;s/int32\([ >*),;[]\)/int32_t\1/g;s/int64\([ >*),;[]\)/int64_t\1/g;s/ uint32(/ uint32_t(/g;s/_uint8_t/_uint8/;s/Uint8_t/Uint8/;s/ft_int64_t/ft_int64/g;s/uint64$/uint64_t/;s/WChar/char32_t/g;s/char32_t char32_t/char32_t WChar/' -i $i; done

Fix: depot-related commands did not validate depot tiles properly (#9948)

The bug comes in two slices:

1) the functions never actually checked if "tile" was a depot tile.
This allowed executing the function on tile 0, where are the
things like shadows of aircrafts are.
2) BuildDepotVehicleList() first checked if a vehicle is in a depot
before checking if it was a primary vehicle. This is invalid
for aircraft.

Fixing the first hides the second, and fixing the second makes the
first non-exploitable. But, fixing both felt like the best thing
to do.

Codechange: use "[[maybe_unused]]" instead of a wide variety of other ways we had

While at it, replace OTTD_ASSERT with WITH_ASSERT, as this
is always set if assert() is valid. No matter if NDEBUG is set
or not.

(svn r14104) -Feature: Add a window for waypoints, allowing to view all the trains having the selected waypoint in their orders.
Changing its name is also supported from the same new window.
Gui based on work done by Satyap, on FS#2025.