#157 Profile change is not possible, privateKey unique constrain violated

[Piotr]

When LDAP authorization is used and new user is created, following fields in sc_users table are set to NULL:
- name
- homepage
- uContent
- privateKey

Then, when user would like to make a change in its profile, values of those fields are changed to '' and unique constrain for privateKey is violated. Because of this, profile change is not possible. User have to generate its private key to make changes in profile possible.