[Libguestfs] [PATCH v2 0/3] p2v: Allow virt-p2v to be built with Gtk 2 or 3.

This is basically the same as what I posted earlier today. The main difference is I split out the GDK thread sychronization (removal of) changes from the other Gtk 2/3 changes, which should make it a bit easier to review. Gtk 3 is still not quite perfect. Apart from the problem with the GtkTextView noted before, there are also vertical alignment and padding problems with labels in GtkGrid widgets. Rich.