Remove spacer when triggering detach.ScrollToFixed event

Hi and thanks for your plugin.

When triggering detach.ScrollToFixed event, spacer is not removed from the dom.
In case of multiple detach / attach event unnecessary extra elements could stay in the dom.

Here a demo : http://jsfiddle.net/Q46Gh/3/

The fix simply remove the spacer when event is triggering.

My editor automatically trim extra whitespace sorry.