Fix marking and deleting listened episodes.
FINALLY removed the crap for storing play location in settings. Now doing it via LINQ.
Show player UI when starting the playback from play queue.
Remove episodes when they are marked as listened, if setting enabled.
Properly update play pos when stopping playback from UI.
Remove commented code.
Open player UI always from play queue items.

Handle marking episodes as listened when we enter the subscription view, and we then read the play queue items.
Handle marking of episodes as listened also when episode is removed from play queue
Add helper methods to remove podcast episodes from the play queue.
Update CHANGES.
Ensure we don't create Settings model the  first time we launch (and have not initialized everything yet)h
Try not to start episode playing timer in vain. And catch player exception.
Fire episode update tick for podcast playing every 2 s instead of 0.5s
Add listened episodes to play queue when we go through the info from backgroud audio player.
Update CHANGES.
Fix non-terminating thread in episode model when podcasts are stopped.
Fix play history view so that we are in sync with saved play pos wrt. now playing and play history item, if they are the same.
Allow episodes to be paused as well when we return to Podcatcher.
Fix updating listened episode when Podcatcher starts.

When podcasts are played and the next episode in the play queue starts to play, at startup we should mark the episodes as listened. Unfortunately there was an issue with updating this infor to DB when we went through this info at startup.
Update play history property for the UI as well, when updating the DB.