Merge pull request #95 from mdlayher/master

Fix video scanning
- Added PlaylistsApiHandler for retrieving, creating, and modifying playlists
- Added or fixed remaining missing Playlist functionality, and tested all functions
- Added Factory class to MediaItem for creating arbitrary media items from item ids
- Fixed selecting PlaylistItem objects
- Sqlite exceptions now also log values along with the query string
- Playlists api call, when used with an id (or with create) now returns the playlist as the only object in the playlists array
- Fixed playlist object doesn't update it's Md5Hash property after updating the database
- Removed dashes in the Playlist Md5Hash