Shiva: Gracefully handle requests for non-existing entities
Shiva: Gracefully handle requests for non-existing entities

Requesting a non-existing artist, album, or track via the Shiva API
used to lead to an uncaught exception and HTTP error 500. Now the
exception is caught and the response is 404 "Not found".

owncloud/music,owncloud/music,paulijar/music,paulijar/music,owncloud/music,paulijar/music,owncloud/music,paulijar/music,owncloud/music,paulijar/music