Bug 20023: Password recovery using email should be case insensitive

Bug 20023: Password recovery using email should be case insensitive

When entering an email to recover the password, a user should not have to know or remember the casing of the given email.

Test
0) enable OpacResetPassword
1) On the OPAC, click "Forgot your password"
2) Enter your email address as in your user account BUT WITH A DIFFERENT CASING
3) Submit.  This will fail.
4) Apply the patch, redo with success.

Signed-off-by: Michal Denar <black23@gmail.com>
Signed-off-by: Marcel de Rooy <m.de.rooy@rijksmuseum.nl>
Signed-off-by: Nick Clemens <nick@bywatersolutions.com>