MediaService Error Strings are thrown as exceptions
CollectionUri strongly typed as Uri
ServiceClient should only throw two types of well defined Exceptions
ServiceNotAvailableException
ServiceOperationException

Closes #19
Fix MultimediaObject PropertyChange Notification for CollectionUri
References #19
Fix: Crossthread when cleaning the DB
Database Check and Repair during app startup
Infrastructure for DB Migrations
References #10
Admin Panel with DB Upload / Download to/from SkyDrive
Closes #10