GLES support and OpenPandora port

This version have

GLES support, with the code between #ifdef HAVE_GLES
It should compile with close to no modification on almost all GLES platform

OpenPandora support. There are some tweaking for the Pandora, mainly some Keymapping and Video resolution.

Toggle Crouch support. When playing on joystick, the crouch can be painfull to use, it could be easier with a toggle crouch (#ifdef CROUCH)

Some ARM (#ifdef ARM) and NEON optim (#ifdef NEON)

There are some Hardwired variables in the makefile to activate all that, I haven't found a way to do something better.