reset loading variable also if only one zone is being updated
reset loading variable also if only one zone is being updated

http://www.pivotaltracker.com/story/show/4593355



opendnssec/opendnssec-svn,opendnssec/opendnssec-svn,opendnssec/opendnssec-svn,opendnssec/opendnssec-svn