Allow additional attribute mappings in ldap

This is needed as a work around for objectclasses that require additional
attributes other than just what is supplied in user_id_attribute and
user_name_attribute.

Change-Id: Ie6cdd0534b8389f62f98fdca7d19bc0feb9c131f
Fixes: bug #1158077
Mark LDAP password and admin_token secret

Add secret=True to LDAP password and admin_token
of keystone configuration.

Fix bug #1172195

Change-Id: I8ef7f705e3f6b374ff427c20eb761892d5146a75
Merge "Mark LDAP password and admin_token secret"
Merge "Allow additional attribute mappings in ldap"