[GSoC status report] Week 11

[Téo Mrnjavac]

During week 11 I have finally finished moving all the forwarders to
Playlist::ProxyBase, without causing any new major breakage. However
more pre-existing breakage has been detected, that will need to be
fixed before seriously working on the GUI. I also cleaned up some
obsolete stuff in Playlist::FilterProxy. FilterProxy will need to
undergo some more refactoring to decouple playlist searching from it.
To take a break from the heavy lifting in the proxies, I have also
implemented a new *temporary* *testing* GUI for playlist sorting. As
you might have noticed it's quite ugly but it should do the job.

As mentioned earlier, and having begun GSoC work almost a month before
schedule, I will now take ~two weeks of break from GSoC work to focus
on my last hard exam. After that I'll fix the remaining
inconsistencies with grouping, searching and navigators and then do
the real GUI.