Ticket 47517 - memory leak in range searches and other various leaks
    
    Bug Description:  Range searches leak memory
    
    Fix Description:  Free the db key, if the key changed between calls to c_get.
    
                      Also fixed a leak when doing a delete operation(retrieving the
                      parent id), and fixed a leak in replication incremental protocol
                      when getting the hostname control.
    
    https://fedorahosted.org/389/ticket/47517
    
    Reviewed by:  nhosoi & richm(Thanks!)
    (cherry picked from commit b737882146e709aa75771168ffd9db63af23e005)