Fixed some typos in the headers.
Replaced SDL_HAPTIC_SQUARE with SDL_HAPTIC_LEFTRIGHT.

We needed a bit, so we're hoping no one needs this effect, especially when
it's fairly close to SDL_HAPTIC_SINE, we hope.

SDL_HAPTIC_LEFTRIGHT maps to XInput's functionality, so this removes the SINE
code for the XInput driver to keep things clean.

This also makes the simplified Rumble API use SDL_HAPTIC_LEFTRIGHT if
SDL_HAPTIC_SINE isn't available, to keep XInput working.

When we break the ABI, and can extend the supported capabilities field from
a Uint16, we'll add SDL_HAPTIC_SQUARE back in.

This patch is based on work by Ethan Lee.
Removed no-longer-necessary comment.
Haptic: Let XInput update effects while they're still running.
Check the return value of glGenTextures()

--HG--
extra : rebase_source : e079554f253890d862bfd5d51d7b229e3fcff3d9
Fixed bug 2024 - Update OSX Joystick code to fully support Saitek p2500 gamepad

Patrick Maloney

Saitek p2500 (Cyborg Rumble Force Pad) has a D-pad, two analog sticks, and numerous buttons.  SDL 2.x on OSX detected everything except the right-side analog stick.  The right-side stick is considered a 'simulation device' with the axes mapped to throttle and rudder.

The patch adds support for throttle and rudder on the HID simulation page.
Fixed whitespace