Add checkconf tests for [#2463]

Add two tests to make sure named-checkconf catches key-directory issues
where a zone in multiple views uses the same directory but has
different dnssec-policies. One test sets the key-directory specifically,
the other inherits the default key-directory (NULL, aka the working
directory).

Also update the good.conf test to allow zones in different views
with the same key-directory if they use the same dnssec-policy.

Also allow zones in different views with different key-directories if
they use different dnssec-policies.

Also allow zones in different views with the same key-directories if
only one view uses a dnssec-policy (the other is set to "none").

Also allow zones in different views with the same key-directories if
no views uses a dnssec-policy (zone in both views has the dnssec-policy
set to "none").

bin/tests/system/checkconf/tests.sh

@@ -12,6 +12,8 @@
 status=0
 n=0
 
+mkdir keys
+
 n=`expr $n + 1`
 echo_i "checking that named-checkconf handles a known good config ($n)"
 ret=0
@@ -549,5 +551,7 @@ grep "exceeds 100%" < checkconf.out$n > /dev/null || ret=1
 if [ $ret != 0 ]; then echo_i "failed"; ret=1; fi
 status=`expr $status + $ret`
 
+rmdir keys
+
 echo_i "exit status: $status"
 [ $status -eq 0 ] || exit 1