cairomm updates

I've been working to get cairomm up to speed lately. I've wrapped pretty much all of the new API from the new cairo 1.2.0 release, so cairomm should be fairly full-featured now.

There are a couple of significant issues to deal with before an official 1.2.0 release of cairomm, the most important of which is that the Cairo::RefPtr implementation leaks memory by not deleting the C++ wrapper object (although the underlying C object does get destroyed). Murray's got a good start on this in bug #7442, so it should be solved pretty quickly. There are a couple other minor things to sort out before I want to declare the API stable, but I'm feeling pretty good about it now.

So if you're interested in having good C++ bindings for GNOME / GTK+, feel free to download the latest cairomm 1.1.10 release and give it a spin and let me know what you think.