Add queuing support.

Also modified a bit the settings menu, and added a setting I forgot before.
Update submodule
Fixed some problem in queuing and added colors
Merge pull request #85 from gtorrent/wip/queuing

Adds queuing
Update submodule to point to fork
Now, for real
Sane way to remove selected torrents
Make the treeview relies only on the torrent pointers instead of their indices
Supports desktop notification.

You will be notified when a torrent finishes/ends.
Currently is adds a dependency to libnotifymm, but it may be moved as
an optionnal dependecy to libnotify in the future.
Move UI settings in -gtk
Somewhat enhanced the graph

I'm not really satisfied with the fill, and I need t find a solution for smooth scrolling.
Uses libnotify instead of libnotifymm
Fix build
Put additionnal settings in the dialog and update .travis.yml
Removed useless things and fixed magnet crash
Should now install libnotify properly
This time fo' real
Merge pull request #86 from fuyukaidesu/master

Notifications.
Fix old reference
Update core