- fixed clang compile error "friend declaration specifying a default argument must be the only declaration".
- Allow generator expressions to be turned off during pk3 building with CMake.
- On Mac OS X, ensure assembly code is disabled by default (since it won't work).
- Fixed: Verbose user info strings were written with an extra backslash
  character between the key and value.
Shuffle FActionMap for better 64-bit alignment.
- Fixed: ACS's PlaySound should mask off the flag bits from the channel
  before passing it to S_IsActorPlayingSomething().
- Fixed: S_IsChannelUsed() is declared as static, so it should be defined
  as such, too.