Implement locking mechanism to only allow one thread to contact echonest for loading Styles, Moods & Genres
use ReadWriteLock instead of Mutex
Add a 'Add to Playlist' entry to the ContextMenu
Merge pull request #175 from xhochy/feature/addtoplaylist

Add a 'Add to Playlist' entry to the ContextMenu
Include --verbose in --help
Merge pull request #176 from xhochy/feature/verbose-in-help

Include --verbose in --help
Escape ampersands in menu entry strings

* Fixes TWK-1172
Merge pull request #174 from tomahawk-player/GeneratorLocking

Implement locking mechanism to only allow one thread to contact echonest...
Add ampersand escaping for Albums and Artists
Merge pull request #177 from xhochy/fix/twk-1172

Escape ampersands in menu entry strings