More framebuffer goodness

Well, for starters, I've reach 100% pass rate with xm-test for the Xend XML/RPC code so I can take a break from that for a little bit while Xen settles down after the huge HVM merge. This leaves some time to work on the framebuffer again.

I talked to Ian for some time today about the framebuffer and in what form it should be merge. Ian has a very valid concern that we don't introduce things that are immediately deprecated (seeing something like the Cirrus FB emulated by the device model as a prime example of this). I think we were able to reach an agreement that as long as the framebuffer can provide good VNC performance (this means ARGB cursor, copy operations, etc.) it's good for quite a while (5 year time frame).

It was quite productive although a bit draining.