[OpenGL] Add preliminary support for GLC
[OpenGL] Add preliminary support for GLC

* config/gen/opengl.pm:
  + Add typedefs needed by GLC character rendering library
  + Mark GLC callbacks as skipped for now

git-svn-id: 6e74a02f85675cec270f5d931b0f6998666294a3@35569 d31e2699-5ff4-0310-a27c-f18f2fbe73fe

ashgti/parrot,ashgti/parrot,ashgti/parrot,ashgti/parrot,ashgti/parrot,ashgti/parrot,ashgti/parrot