Allow more choices on mobile client quality playback

By default I stream my internet quality at 1080p 8mbs so my mom can watch a good quality picture. but when I go jogging or out for a walk with my iphone and want to watch videos without constant pausing, the only video options available to me are basically 480p, 1080p or original.
it would be nice if i could choose watch at 720p on my phone instead of an extremely blurry 480p or a big slow 1080p.

2021 clean-up: implemented (quality selection will show a context specific subset of the available options – at the bottom of the list of options there’s an Show All option)