stalled transfers.

1435.   [bug]           zmgr_resume_xfrs() was being called read locked
                        rather than write locked.  zmgr_resume_xfrs()
                        was not being called if the zone was being
                        shutdown.

1434.   [bug]           "rndc reconfig" failed to initiate the initial
                        zone transfer of new slave zones.
developer: marka
reviewer: explorer