libvirt 1.2.0

I hope the commit message is the correct format. I held back on this bump request because I wasn't sure how to proceed but I haven't had a chance to ask in the proper channels so I'll use the pull request to ask...

With 1.2.0, we (libvirt upstream) stripped out the Python bindings into their own package which we've made installable via pip. Do you want me to add the bindings as another package or just let people install them via pip?