Data.FormValidator patch for email tests

[Mark Stosberg]

Here's a patch for Data.FormValidator that adds several tests for
e-mail constraint. One test is failing because of an apparent bug in
the software. This doesn't work:

support('email')

but it is documented to work that way.

http://mark.stosberg.com/javascript/dfv_email_tests.patch

Thanks for this port of Data::FormValidator!