Save user attributes on subsequent calls to login.
    
    When a login comes in via the remote_login() call no
    user attributes are set. These may be later filled in by
    a subsequent call to login() after the info plugins are
    called but a short-circuit in that function exits if the
    user matches the current session.
    
    Add an extra conditional such that if the user matches,
    userattributes are passed in and the current user attributes
    for this user is empty then save the new data.
    
    https://fedorahosted.org/ipsilon/ticket/86
    
    Signed-off-by: Rob Crittenden <rcritten@redhat.com>
    Reviewed-by: Nathan Kinder <nkinder@redhat.com>