Widget to toggle mute of pulseaudio default source

[lnqs]

I created a new widget to display and toggle the mute state of the default pulseaudio source.
No idea if this is interesting for upstream as it's quite specific to the Linux desktop due to it's dependency to pulse.
Anyway, if it is I'm looking forward for feedback to get it merged :)

[zMoooooritz]

Just some thoughts from my side:
This does introduce the concept of a system status dependent 'state-full' widget for one specific application i.e. exchange images according to the mute state.
In #49 such a feature (for conditional output and more) has been requested and I think this would be awesome but does require quite some changes.
In case we would have that feature we could achieve the functionality of your widget by calling local bash scripts via exec.

[lnqs]

Having that feature from #49 would be really nice as it gives a lot of flexibility.
I'd prefer a implementation accessing system state (pulse in this case) natively above calling commands anyway.

Probably the best way on a longer term would be to have a thin base application and a plugin system to allow more specific widgets to be loaded optionally.

[liljenstolpe]

This needs to be re-based before merge. There are TTF font issues that have been fixed in upstream. The rebase causes no errors.

[muesli]

This needs to be re-based before merge. There are TTF font issues that have been fixed in upstream. The rebase causes no errors.

I can rebase this in GitHub, I just need to find the time to properly review it this weekend 😃