[SAC] Userid registration with email confirmation is ready for test

[Sandro Santilli]

I've worked on a version of the user registration that includes
an email confirmation step. The form doesn't change, but on submit
a confirmation email is sent.

Following the link sent via email triggers actual user creation.

Tests are welcome:
http://www.osgeo.org/cgi-bin/ldap_create_user_emailconfirm.py?mantra=

NOTE: you need to append the mantra value there

--strk;