XUProxy status update

[andrew_w]

It took me a little bit longer than expected, but I think that I've fixed all the major issues now, and will hopefully be ready to release 0.1.0 in the next few weeks. I think that all that I have left to do is write some decent unit tests for the filtering library in order to make sure that it is actually working properly. As I said before, this release will be far from feature complete (beta if you want to be really generous, but alpha would probably be more accurate), but basic Proxomitron-compatible header and content filtering should be working reasonably well.