- alternative configuration using GLEW to get extension functions. This requires GL 2.0, though so it won't be promoted to the mainline for the time being.
- removed all pre GL 2.0 support.
Merge branch 'master' into GLEW_VERSION
- got rid of a lot of stuff that's no longer required with GLEW.
- replaced GLUs texture scaling with our own function. This is only used to scale down textures larger than what the hardware can handle so we do not need a dependency to an essentially deprecated library for it.
Merge branch 'master' into GLEW_VERSION
Added static RNGseed control
Don't change RNG in demos incase they are static
Make sure use_staticrng is false if not needed
Merge branch 'upstream' of https://github.com/Edward850/zdoom
- fixed: since A_LightGoesOut alters a sector's floor plane it must also alter the TexZ for that sector's floor.
Merge branch 'master' of https://github.com/rheit/zdoom
fixed some issues with reviving monsters

- fixed: Thing_Raise didn't properly set the spawn health.
- fixed: Thing_Raise did not the CanRaise state flag.
- fixed: Reviving a monster must also reset the damage type.
- fixed: Thing_Raise reset the actor after calling the raise state, but it should be before, just as the Archvile code is doing.
- consolidated some common code of Thing_Raise and Archvile resurrection into AActor methods.
Stop NetUpdate from corrupting demo playback
Changed the default movebob.
Small cosmetic changes to the Options menu

- Restored playermenu.cpp to pristine state.
- Offset the OptFont cursor and slider to compensate for weird font scaling.
Reimplemented gun offset features in ACS.
- removed redundant variable.
- typo in resurrection code.
made some changes to turn the CF_INTERPVIEW flag when changing angles into an op-in feature instead of making it automatic.
Merge branch 'interpview_optin'
- added new ChangeActorAngle/ChangeActorPitch ACS functions because the new required 'interpolate' parameter cannot be added to the existing SetActorAngle/SetActorPitch functions without breaking old scripts.