i15-1: Setup & Queue interaction improvements

[EmsArnold]

A number of improvements can be made between the Setup and Queue pages.

• Currently queue tasks are added to the beginning of the queue, they should be added to the end by default
• "Playlist" item order from the setup page is not always preserved when added to the queue. Ordering commonly observed to shift when there is a task in progress in the queue, but seems stable if the queue is empty

[DominicOram]

#95 fixes the first item