Vim-style keybindings for text editing.

I think it’d be great to have Vim-style keybindings in this app. It'd make text navigation and editing so much faster and more efficient, especially for developers and powerusers who works with text a lot - which seems to be the market Floaters is targeted towards.

It’d also be awesome if this were an optional feature, so people could turn it on if they want to. A lot of other tools offer similar functionality, and adding it here would make the app even more versatile.