[Feature Request] Navigating by keyboard in settings

[liljom]

Would be nice if a subsetting could be easily closed by Esc key, eg here:

Esc would act like clicking the Close button in top-right. The only option at the moment is to move the mouse to the button and click it. Esc could also take one level up in the settings.
Tab and Shift + Tab could jump between left panel (where Networks, Bluetooth, Destop ... are) and right part (where the settings are), and the arrows could navigate inside the elements.
Mouse back button would be also appreciated.