Remove momentum reduction in CA_JUMPTHOK

Also add new multiability handling for it
Merge branch 'master' into next
Merge pull request #28 from wolfy852/master

Remove momentum reduction in CA_JUMPTHOK
SRB2 2.1.11 release
Merge branch 'next'
evil changes
SDL2: Fix 320x200 mode
SDL2: Reimplement some stubbed commands

Also remove some unnecessary functions.
SDL2: Do not use xinput, force directinput

Fixes axes issue with xinput controllers.
SDL2: Add 1600x1200 mode
Add debug lines.
Why the #@!& is M_CheckParm("-opengl") always returning 0 with SDL2?
Work around the myargc screwup by restoring after W_InitMultipleFiles.
This makes OpenGL work on SDL2 when using certain custom wads.
I still can't figure out how myargc gets set to 0 in the first place, but it seems myargv isn't getting screwed as well.  I should probably check that.  If you hear nothing else of the matter, then myargv is probably not being screwed.
Merge branch 'ogl_linux64_fix' of https://github.com/ilag11111/SRB2 into ogl_linux64_fix