Added Fuzzy Search Capabilities to File Filter

Websites in development mode often use many static assets, including javascript and CSS files, which become difficult to scroll through quickly.  Firebug's existing file filter allows you to find files by searching for an exact file path match, but often this is too slow if this needs to be done many times per day.

Editors like TextMate and Sublime Text 2 utilize [fuzzy searching](http://en.wikipedia.org/wiki/Approximate_string_matching) to make finding files a treat, and this is what I've added to Firebug's file filter.  With only about *40 lines of code*, users can now find files that include the correct sequence of characters but possibly with other characters between:

![1](https://f.cloud.github.com/assets/795979/595930/73af1a3a-cb42-11e2-85ae-efea27ec8acb.png)

In the example above, notice that I no longer need to type the full name of the file to have the correct file display as a search result.  And further, both uploadifive and uploadify scripts appear next to each other, making it easy to see all related files **without needing to remember** the exact name of the file beforehand.

Even better, we can also now **filter by the entire file path** by including '/' forward slash characters in our search token:

![2](https://f.cloud.github.com/assets/795979/595931/927f4098-cb42-11e2-9f16-a49ae33699fa.png)

Using three simple characters 'fiv' above, I've limited my query to the uploadifive folder.

I'm really hoping this will be added to the trunk, since this will save developers little bits of time *many many* times over the course of many hours of daily debugging time.