Close tags (fixes configure being broken in IE8)

Unless you're creating an element by itself
(which gets passed to document.createElement)
you should add closing tags otherwise it will break in IE8.

See also:
http://bugs.jquery.com/ticket/1587
http://bugs.jquery.com/ticket/12581
Merge pull request #2 from johnnyg/close-tags

Close tags (fixes configure being broken in IE8)