Re-Add Ability to add a video to the Queue

[kingargyle]

For individual videos need to be able to add them to the queue.

[kingargyle]

This is implemented with issue #371 being re-added. The internal player does not yet support looping through the videos for playback so will keep this open until that is completed.

[kingargyle]

This relies on issue #388 to be completed first.

[kingargyle]

Related to #388 and emby playlist support