Bug 965970 - Do not chown /var/named

https://bugzilla.redhat.com/show_bug.cgi?id=965970

Chowning /var/named introduced avc denials when restarting bind, Change
the chown to chgrp.
Merge pull request #21 from detiber/bz965970

Bug 965970 - Do not chown /var/named