Show current shortcut in Settings.  Add options to leave windows in current position, focus new window.

Hey - this extension was almost everything I was looking for to get around this shortcoming of Chrome on Windows, but I needed options to leave the base window as it was, and to focus the new window instead.  With those implemented, I also made a quick change to show the current key-binding in the settings menu.  Please go ahead and bring in any changes you like - I suspect they're useful additions to the extension. ~ James