All users should be able to change their password, not just power users

To reproduce:

1. Log in with a member.
2. Go to Home > Profile.
3. Click Actions > Change password.
4. Type the new password and save.
   -> A feedback message says the password was changed.
5. Log out.
6. Log in using the new password.
   -> Login fails.
7. Log in using the old password.
   -> Login succeeds.

Currently, only power users can successfully change their password.