Add swap_interval support.

Again, mostly useful for 120Hz monitors, and/or playing content which is
a fraction of monitor refresh rate.
Add window scale x/y and crop overscan options.
Set swap interval correctly in gl_init().
fix xinput (again)- repair multiple pads support
Merge pull request #295 from pinumbernumber/xinput-multipad-hotfix

Another tiny XInput hotfix
Save input_playern_joypad_index on exit
(Apple) Reorganize source tree
(Overlay) Add basic analog support
(OSX) Set player ID LEDs on connected PS3 pads
(OSX) Update gfx_context:
   Now resizes window when asked
   Displays proper title in window
   No longen prints Cocoa warning at start up
   Now supports the pause_nonactive feature
Hardcoded joypad config fallbacks, and required changes to config_file
(Overlay Analog) Coding style fixes
(Analog Overlay) Add a saturate_pct key to descibe the point at which an analog hitbox will return the max analog range
Merge pull request #298 from libretro/overlay_analog

(Overlay) Add basic analog support
Fix compilation error introduced by analog overlay changes
Merge pull request #300 from MP2E/master

Fix compilation error introduced by analog overlay changes
Various fixups to the internal autoconf system
(QNX) Build Fix
(QNX) Fix the build fix, I am an idiot
(OSX) Hide mouse cursor in fullscreen mode