Workaround for jQuery Autocomplete Plugin mustMatch Fail on Commas
The jQuery autocomplete plugin is quite nice, and we use it a fair bit on DealBase. However, what I found was that if you set the mustMatch option, your text cannot contain commas, colons, and a few other punctuation (and maybe other) characters. For some reason that I've yet to track down (debugging through many nested anonymous functions and callbacks has yet to yield an answer), it thinks it changes at some point to not think it's a match. A good example of this is if you allow a user to type in a city name, but you want to show them matching cities with the state and/or country included, to disambiguation. E.g. you may have Portland, Oregon and Portland, Maine (not to mention the few Portlands in Australia :)
matchSubset option to true. This allowed it through, retaining the full text of something like "Portland, Oregon". According to the plugin's docs, matchSubset should only come into play when using the cache, which we don't use (because we limit results to 20 items, and often there are more than 20 matches, e.g. a user types "new" or "las" or something - many cities will match). 
