[cairo] glitz backend

[David Reveman]

I've now committed the new glitz backend to cairo, so CVS versions of
glitz and cairo should now be in sync again.

The new glitz backend still needs some work but it will do for now. e.g.
there's no good way for controlling anti-aliasing and it will actually
produce incorrect rendering in a few cases right now as it thinks that
cairo is giving it non-overlapping trapezoids but that's not true yet.

btw, latest version of glitz (0.2.2) is available as a snapshot.
 
-David