Those extensions have become part of ARB about 15 years ago and most if
not all video cards still in use should support the ARB versions. I
believe that at least parts of this code were disfunctional.
This removes the need to define the old qgl function names to the
official OpenGL names. The OpenGL functions are now called directly
without any abstraction.
With this change the "refresh" make target doesn't any longer exists.
It was merged into the "client" target. One will need a "make clean"
before building yQ2 after this change.
