TODO

* Update the autocomplete to use the new jQuery UI autocomplete widget. The 
current one is deprecated, though still functional.

* Add keyboard shortcuts for highlighting tags to remove them upon backspace.

* minLength for autocomplete

* hide the singleFieldNode

* add quotesAllowed option (or quotedSpacesAllowed)

* autogrow the input (http://stackoverflow.com/questions/931207/is-there-a-jquery-autogrow-plugin-for-text-fields)