Include a space before trailing /> of empty HTML elements

This minor HTML formatting issue was brought to my attention during a recent PPV: 

"In self-closing tags a blank space should precede the forward slash, even though it is allowed to omit that space in XHTML. Still, there are a few (exotic) browsers out there which tend to ignore the tag altogether."

The element in question was a <col> tag. I added the space for <col /> and found another case where the space was missing from an <hr /> tag.