Get rid of the 2 CPUID flags and combine them with SSE in one
implementation.
SSE flags can now be set on all x86 and x86_64 platforms -
independent of -ffast-math.
Helper defines borrowed from STREFLOP.
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.