Added SVGElement to JSHint globals list.
Added SVGElement to JSHint globals list.

This needs to be defined because JSHint 1.1.0 does not include the SVG
interfaces in the browser globals collection. If/when JSHint adds SVG to
the browser globals this commit should be reverted.

Part of issue #61.

jasco/jquery-powertip,stevenbenner/jquery-powertip,erthalion/jquery-powertip,stevenbenner/jquery-powertip,erthalion/jquery-powertip,jasco/jquery-powertip