Merge of GL-AutoChoose.

This branch is the final step of fully supporting both OpenGL and OpenGL ES in the same binary.
This of course only applies to EGL and won't work for GLX/AGL/WGL since they don't really support GL ES.
The changes here actually aren't too terrible, basically change every #ifdef USE_GLES to a runtime check.

This adds a DetectMode() function to the EGL context backend.
EGL will iterate through each of the configs and check for GL, GLES3_KHR, and GLES2 bits
After that it'll change the mode from _DETECT to whichever one is the best supported.
After that point we'll just create a context with the mode that was detected

Source/Core/DolphinWX/GLInterface.h

@@ -51,11 +51,6 @@ typedef struct {
 #endif
 } GLWindow;
 
-enum GLInterfaceMode {
-	MODE_OPENGL = 0,
-	MODE_OPENGLES2,
-	MODE_OPENGLES3,
-};
 extern cInterfaceBase *GLInterface;
 extern GLWindow GLWin;