* Breaks every other game except Duke unless/until they get migrated. Done for the purpose of demonstrating PR #244.
# Conflicts:
# source/build/src/timer.cpp
# source/games/duke/src/game.cpp
* Build timer still requires initialisation due to multiple `timerSetCallback()` that still need to work.
# Conflicts:
# source/core/menu/menu.cpp
# source/games/duke/src/game.cpp
* rewrote all uses of timerSetCallback. Most were unnecessary or long obsolete, the sound updates need to run per frame, not per tic and the UI tickers need to be handled in the main loop anyway.
* Use a more precise timer to animate the menu transition.
* uncouple other menu animations from the game timer.
Avoid passing this anywhere in the client code. It should only be set right before rendering the 3D view and the only code using the base palette should be the 3D renderer and hud_drawsprite.
Also make the palette override CVARs 3D view only in debug mode.
The checks for game pause were totally inconsistent, so now there is a utility function that tells whether the game is supposed to run or not.
pause can also take 3 values now - 0 for no pause, 1 for pause from opening the menu or console or 2 for hitting the pause button.
If this is supposed to be made customizable it has to be done very differently.
# Conflicts:
# source/games/duke/src/game.cpp
# source/games/duke/src/sbar.cpp
