Merge pull request #156 from Aloshi/master

Replace GBA core with the gpSP emulator
Added option for enabling/disabling variable HDMI resolution, bug fixes, minor enhancements
Updated the RetroArch configuration when using SNESDev
Add db9 joystick driver.
Merge pull request #159 from marqs85/db9_gpio_rpi

Add db9 joystick driver.
Added SNES9X emulator
Added PiSNES emulator.
Add runcommand.sh autodetect HDMI support, as discussed in issue #173.
You might want to test this on a non-HDMI setup - I don't have one, but it should work...
New arguments are now 1 = auto, 2 = off, 3 = force on.