Suspend

[flyingpie]

Adds the ability to "suspend" and app; detaching it from WTQ's control, reverting back to regular drag-around window.

The current prototype does this by double-tapping the toggle hotkey, and resumes when just tapping the hotkey.

I'd like to look into the hotkey binding for this a bit, to potentially support stuff like:

• Using dedicated hotkey for detach/attach;
• Using double-tap for different actions (like quick switch between 2 most recent apps).