Add more keybindings

It would be good to have keybindings for opening the app drawer and navigating the homescreen (Switching between homescreens, As well as for example pressing a keybinding to go to the homescreen while running an app), and opening the top quicksetting panel.

Not only would this be great for the upcoming Pinephone keyboard addon (and possibly other phones such as the Fxtech in the future), but this would be useful when the phone is hooked into a monitor.