Bug 19907: Fix email validation in patron edit form

Bug 19907: Fix email validation in patron edit form

Test plan:
0) Confirm that email validation is not working in add/edit patron form
1) Apply the patch
2) Edit/add patron, the e-mail validation should be working now
3) Ensure the password validation is still working (use test plan from
    bug 19908)

Signed-off-by: Katrin Fischer <katrin.fischer.83@web.de>
Signed-off-by: Nick Clemens <nick@bywatersolutions.com>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>