intg: Create FakeAD class based on openldap
    
    FakeAD is openldap with ldif schema which allows to load static data
    from real AD. Instance of class will also contain some predefined
    users/groups which can be used for basic sanity testing in sssd of AD features.
    
    Reviewed-by: Fabiano Fidêncio <fidencio@redhat.com>
    Reviewed-by: Jakub Hrozek <jhrozek@redhat.com>
    (cherry picked from commit 36df33cd44774a5b5eab52ab222bcd3240b3ca5a)