Add quick access bar like game capture

[BuyMyMojo]

Simple enough to explain:

[bozbez]

I had a look into this during initial development, seemed that the current quick bar is more or less hard-coded into the UI code although I could be wrong. This would make it a bit of a pain to implement without upstreaming the plugin itself.

Alternatively I have no idea if you could do this using a frontend plugin (or maybe even the frontend API but that seems unlikely).

[ASchneiderBR]

This would be really useful for quick changing. Also, having the audio capture plugin capturing the same window as the game capture would be great!