Fix null pointer on NowPlaying Popup
Merge branch 'develop' of https://github.com/abarisain/dmix into develop
JMPDComm: Fix replacing artist with album artist in the album object.

This is a regression of 51cecb7 where an attempt to set a new artist
object in an album object was attempted directly during iteration
rather than by method parameter. This also corrects the album artist
identifier, and renames the method to more accurately reflect it's
purpose.
Merge branch 'develop' of https://github.com/abarisain/dmix into develop
fix NPE in UpdateTrackInfo