Only call 1 UI refresh loop EVER. And never let it die.

Set a switch in Gst.init. Moved the ui refresh loop from play to song_start. Made update_song_row always return something. ui_loop runs once the 1st time it's called in start_song, flips the switch to True and can never be ran again and since update_song_row always returns something the loop never dies. Basically hit it and forget it. It's called once and only once, and never dies. No more redundant ui loop calls.