We now have back a real BufferModel. It's basically a ProxyModel to

We now have back a real BufferModel. It's basically a ProxyModel to
the recently introduced NetworkModel.
Activity displays in the BufferViews are now a bit crippled (new
Activity levels will be shown even when the buffer is selected).

Now We can Use The Nickviews with the NetworkModel and get Rid of the
QtGui Dependency in the Client.