the default value of dnssec-validation is 'auto', which causes
a server to send a key refresh query to the root zone when starting
up. this is undesirable behavior in system tests, so this commit
sets dnssec-validation to either 'yes' or 'no' in all tests where
it had not previously been set.
this change had the mostly-harmless side effect of changing the cached
trust level of unvalidated answer data from 'answer' to 'authanswer',
which caused a few test cases in which dumped cache data was examined in
the serve-stale system test to fail. those test cases have now been
updated to expect 'authanswer'.
- Check that an NS in an authority section returned from a forwarder
which is above the name in a configured "forward first" or "forward
only" zone (i.e., net/NS in a response from a forwarder configured for
local.net) is not cached.
- Test that a DNAME for a parent domain will not be cached when sent
in a response from a forwarder configured to answer for a child.
- Check that glue is rejected if its name falls below that of zone
configured locally.
- Check that an extra out-of-bailiwick data in the answer section is
not cached (this was already working correctly, but was not explicitly
tested before).
