This changes all GLES code to use the OpenGL function names instead of
the cogl_wrap_* names. For GLES2 we now define the OpenGL name to point
to the wrapper, as opposed to defining the wrapper to point to the
OpenGL name for GLES1.
I've also done a quick pass through gl/cogl.c and gles/cogl.c to make
them more easily comparable. (most of the code is now identical)
e9a9acd28d