Add support for managed status bars.

More goodies, as promised. :)
The status bar is the name for the menu bar in OS X (See [`NSStatusBar`](https://developer.apple.com/library/mac/documentation/cocoa/reference/applicationkit/classes/nsstatusbar_class/Reference/Reference.html)) so the usage here is ambiguous. All instances of 'status bar' should be changed to 'bottom bar'.