Bug 14509: Reject invalid passwords

Bug 14509: Reject invalid passwords

Bug 10177 rejects password with leading or trailing whitespaces, but
only on the member-password page.
It's not consistent to only do this check on 1 place.
This patch adds the check for the 2 other places: memberentry and at the
OPAC.

Test plan:
1/ Edit a patron and set a password with leading and/or trailing
whitespaces. You should not be allowed to do it (no server side check).
2/ Same at the OPAC ("Change you password" tab). Here there is a server
side check.

Followed test plan. Works as expected.
Signed-off-by: Marc Véron <veron@veron.ch>
Signed-off-by: Marcel de Rooy <m.de.rooy@rijksmuseum.nl>
Signed-off-by: Tomas Cohen Arazi <tomascohen@unc.edu.ar>