DOM utilities: potentially more efficient adding/removing of class names

[FND]

Hey guys,

I just stumbled across Webshots's helper functions for adding and
removing class names:
http://p.webshots.net/js/chromeUtil.js
(Look for hasClass(), addClass(), delClass() and setClass() - whereas
the latter is optional.)

They are RegEx-based, so they *might* be more efficient than TW's
current equivalents.

I'm not an expert on this, but I thought it was worth mentioning.

-- F.