Replace "master/slave" terminology in tests

Replace most "master/slave" terminology in tests with the preferred
"primary/secondary", with the following exceptions:

- When testing the old syntax
- When master is used in master file and master file format terms
- When master is used in hostmaster or postmaster terms
- When master used in legacy domain names (for example in dig.batch)
- When there is no replacement (for example default-masters)

bin/tests/system/staticstub/tests.sh

@@ -113,7 +113,7 @@ done
 grep "2nd sub test data" dig.out.ns2.test2.$n > /dev/null || ret=1
 # re-enable the parent
 copy_setports ns3/named.conf.in tmp
-sed 's/EXAMPLE_ZONE_PLACEHOLDER/zone "example" { type master; file "example.db.signed"; };/' tmp > ns3/named.conf
+sed 's/EXAMPLE_ZONE_PLACEHOLDER/zone "example" { type primary; file "example.db.signed"; };/' tmp > ns3/named.conf
 rndc_reload ns3 10.53.0.3
 if [ $ret != 0 ]; then echo_i "failed"; fi
 status=`expr $status + $ret`