Fixed -Wreorder warnings (hopefully the last?), also several potentially
uninitialized variables.
In SetupPixelFormat_OGL() Assert if gap_iDepthBits ends up being 0.
Small adjustments to cmake warning settings for gcc/clang
This was a _ton_ of changes, made 15 years ago, so there are probably some
problems to work out still.
Among others: Engine/Base/Stream.* was mostly abandoned and will need to be
re-ported.
Still, this is a pretty good start, and probably holds a world record for
lines of changes or something. :)
