renamed IOS_* functions in cl_input.c to CL_*.

- The following were reported by Zack Middleton (zturtleman), see the Issues page for more info
removed GLimp_* from cl_ui.c and cl_cgame.c, GLimp_Release doesn't get called (not sure what this does exactly may be re-implemented).
moved vidRotation out of glConfig_t.
fixed Sys_PIDFileName and removed using PID file on iOS.
removed unneeded BUILD_IOS_BASEGAME from README.
stubbed Sys_Dialog().
use __arm__ in q_platform.c instead of IOS.
undo iOS changes to cinematic drawing.
undo keyCatchers move in cl_keys.
use #ifndef IOS to remove minimize command in gl1/gl2 renderer.
removed IOS ifdef's in vm_none.c, need to remove this from iOS build project and use NO_VM_COMPILED.
stubbed GLimp_Minimize if its not defined
make touch menus draw based on active menu
	(this means that touch buttons need to be drawm in the same order as the actual buttons are drawn)
rename IOS_* -> CL_*
temp stub for GLimp_Minimize
updated README