* Replaced regex for URL method, thanks to the contribution by Scott Gonzalez, see http://projects.scottsplayground.com/iri/
* Improved email method to better handle unicode characters
* Fixed error container to hide when all elements are valid, not only on form submit
* Fixed String.format to jQuery.format (moving into jQuery namespace)
* Fixed accept method to accept both upper and lowercase extensions
* Fixed validate() plugin method to create only one validator instance for a given form and always return that one instance (avoids binding events multiple times)
* Changed debug-mode console log from "error" to "warn" level