Ticket 47877 - check_and_add_entry fails for changetype: add and existing entry
    
    Bug Description:  If an ldif file in the updates directory contains
    			changetype: add, the add fails if the entry
    			already exist
    
    Fix Description:   ignore existing entries also in case of
    			explicite changetype
    
    https://fedorahosted.org/389/ticket/47877
    
    Reviewed by: ?