Draft: batterymonitor: Active status on inhibitions

With this one, I'm not sure if the average user would find this useful or rather distracting: If there are any inhibitions, like VLC playing, OBS recording or when in a Zoom meeting, the batterymonitor applet would become active. On my PC (which doesn't have a battery), this results in the applet appearing in each of these circumstances and disappearing when all inhibitions are gone. I personally like this, because nothing else (e.g. the icon itself) conveys information about inhibitions – otherwise I could just set the applet to always be visible. Alternative approaches include adding a separate applet for inhibitions or making the behaviour user-configurable.