`_glDrawRangeElements@24'
Resolve glDrawRangeElements with cogl_get_proc_address instead of
calling it directly because functions defined in GL > 1.1 are not
directly exported under Windows.
* clutter/cogl/common/cogl-mesh.c: Use the function pointer from
the context
* clutter/cogl/gl/cogl-context.c (cogl_create_context): Initialise
function pointer.
* clutter/cogl/gl/cogl-context.h (CoglContext): Add a function
pointer
* clutter/cogl/gl/cogl-defines.h.in: Add a typedef for the
function pointer.
* clutter/cogl/gl/cogl.c (_cogl_features_init): Resolve
glDrawRangeElements