Pulse Audio Control Widget (mute/unmute only atm)

[Someone0nEarth]

Hi, I wrote a widget for controlling Pulse Audio input clients. I talked to muesli and we decided to split up my commits to several smaller PRs. This is the first one.

You can see the current state of the Pulse Audio Widget here: https://github.com/Someone0nEarth/deckmaster/tree/develop

Have fun, Someone