Add listener for media play pause

[maxkraft7]

The key MediaPlayPause (https://www.toptal.com/developers/keycode/for/media-play-pause) could be utilized. It gets aleady used by most webbrowsers if you have streams running.

[nukeop]

I wanted to add it some time ago, but it doesn't work with https://www.npmjs.com/package/mousetrap which we use for keyboard shortcuts. I would be happy to merge this if somebody implements it.

[AnthonyMarin]

Turns out Mousetrap allows you to add keycodes. I just found the keycodes for the major media buttons and added them using mousetrap.

[nukeop]

Implemented