* Xbox GDK support (14 squashed commits)
* Added basic keyboard testing
* Update readme
* Code review fixes
* Fixed issue where controller add/removal wasn't working (since the device notification events don't work on Xbox, have to use the joystick thread to poll XInput)
* Add initial support for the Nokia N-Gage
* N-Gage: disable clipping for the time being, issue needs to be resolved later
* Move va_copy definition to SDL_internal.h
* Move stdlib.h include to SDL_config_ngage.h, much cleaner this way
* Remove redundant include, add HAVE_STDLIB_H
* Revert "N-Gage: disable clipping for the time being, issue needs to be resolved later"
This reverts commit 4f5f0fc36cc7f34fad05e45671dfa7b8dc32fd51.
* N-Gage: fix clipping issue by providing proper math functions
The internal function SDL_EGL_LoadLibrary() did not delete and remove a mostly
uninitialized data structure if loading the library first failed. A later try to
use EGL then skipped initialization and assumed it was previously successful
because the data structure now already existed. This led to at least one crash
in the internal function SDL_EGL_ChooseConfig() because a NULL pointer was
dereferenced to make a call to eglBindAPI().
