Add a connection chooser menu on the bottom panel

[PauloGDPeixoto]

Konga is awesome, but there is one little thing that sets me back a lot of time: having to go into settings to choose the connection.
I use Kong in several independent clusters and it would be nice to have a quick way to alternate connections, let's say, a menu that could open when you click the current connection on the status bar. In the same sense that there are links to the github page and to the github issues page, it would be a nice feature that would immensely improve the usability of Konga.

[pantsel]

@PauloGDPeixoto ,

Great idea! Definitely gonna apply it on the upcoming version!

Thanks!

[pantsel]

@PauloGDPeixoto ,

check out the new release https://github.com/pantsel/konga/releases/tag/0.6.3