Display menu in title bar for non-maximized windows

The global menu hinders user productivity when the application isn't maximized, particularly on large displays. If we use the active window's title bar instead, we don't add significant distance or keystrokes to tasks. We also gain ease of implementation: we're only dealing with the focused window and can accommodate touch, click-to-focus, and focus-follows-mouse. To ensure we don't lose the ability to move windows by the title bar, we add a single button (which also exposes the existence of a menu for the application to the user). Example: "X - [] > Window Title" becomes "X - [] > Menu1 Menu2 ... MenuN" when the user clicks on or hovers over the ">" button. Please see my comments in https://answers.launchpad.net/ubuntu/+source/unity/+question/153832 . Thank you!