Don't block the UI thread when adding torrents by magnet link.
Add associate button in the preferences.
Remove redundant code in the AddTorrentDialog and re-do it with DependencyProperties and UICommands, while removing uncessary element names.

Because why not.
Improvements in the RSS feeds manager.

But it's not near finished yet.
Fix loading magnet message in the AddTorrentDialog.
Add support for enclosures in rss items.

It's not tested though.
Improvements in the feed manager.
Merge pull request #33 from diantahoc/master

I changed some stuff in AddTorrentByMagnet