initial port to sdl 2.0, still segfaults on first keyinputs
video and audio stuff works. Key processing needs to change
uncrustify sdl2 stuff
Merge branch 'master' into sdl2

TODO:
	mousewheel movement was disabled in sdl_input.c
	r_mode -2 was disabled in sdl_glimp.c
	joystick was disabled

Conflicts:
	src/sdl/sdl_gamma.c
	src/sdl/sdl_glimp.c
	src/sdl/sdl_input.c
	src/sys/sys_platform.c
misc: CMake doesn't include a find module for SDL 2 yet
Merge branch 'master' into sdl2

Conflicts:
	src/sdl/sdl_glimp.c
	src/sdl/sdl_input.c
client: fixed blank window with SDL2, refs #332
client: removed various hacks for SDL 1.x, refs #332
client: fixed mouse warping with SDL2, refs #332
client: use SDL 2 instead of SDL 1.2, refs #332

https://github.com/ioquake/ioq3/commit/f478761e07e94b3765b16b2e7d083624a7b05f3a
client: SDL 2 clean up, refs #332
Merge branch 'master' into sdl2
renderer2: clean up of renderer initialization, refs #332, refs #321
Merge branch 'master' into sdl2
renderer2: removed SMP, refs #321
renderer2: removed unused variables and functions, refs #321
client: detailed IN_PrintKey output, refs #332
Merge branch 'master' into sdl2

Conflicts:
	src/renderer2/tr_backend.cpp
	src/renderer2/tr_shade.cpp
misc: updated travis build to use SDL 2
travis: added SDL2 ppa