Changing idSession would break the interface for Game DLLs, making the
existing ports of Mods incompatible.
Luckily we have idCommon::GetAdditionalFunction() for cases like this..
Also added a check for WEAPON_NETFIRING in idWeapon::EnterCinematic(),
I got an Assert() there in Debug builds.
Running the Demo seems to work now, at least I could finish it without
any problems (ignoring some warnings in the console)
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.
