New CVar "in_kbd" to set the layout for the keyboard. SDL 1.2
doesn't offer any way to determine it, and we need this feature
to use the same key for toggling the console independent of the
keyboard layout.
The old "in_nograb" from the Linux backend is still supported.
Use SDL to set video modes, get a GL context and detect the
amount of VRAM.
As with the Linux GLimp implementation, sys_videoRam can be used
in case the SDL detection fails.
Don't include the lazy precompiled.h everywhere, only what's
required for the compilation unit.
platform.h needs to be included instead to provide all essential
defines and types.
All includes use the relative path to the neo or the game
specific root.
Move all idlib related includes from idlib/Lib.h to precompiled.h.
precompiled.h still exists for the MFC stuff in tools/.
Add some missing header guards.
This kills the funky GL logging stubs, which unnecessarily
complicates the build process (think future cmake).
As for logging GL calls: Use apitrace for that
https://github.com/apitrace/apitrace
