Add /lofi command

[e-caste]

This command should give only logged in users the ability to:

• [ ] start streaming the ChilledCow "lofi hip-hop beats to relax and study to" via the Raspberry Pi speakers
• [ ] turn up or down the speakers volume

/lofi should then spawn 3 contextual buttons:

• "Play" if the stream is paused or "Pause" if the stream is playing -- first row
• "-" to turn down the volume -- second row
• "+" to turn up the volume -- second row

A quick duckduckgo search returned this method to stream audio from youtube in Python: https://stackoverflow.com/questions/49354232/stream-youtube-audio-from-python-using-url-without-downloading-python#49354406