* middleware/file: don't reload zone when SOA isn't changed
Give Parse an extra argument which is the SOA's serial, if > 0 we check
against the just parsed SOA and then just return.
Most notable use is in reload.go which is both used in the file and auto
middleware.
Fixes#415
* PR comments
Fix the delegation handling in the *file* and *dnssec* middleware.
Refactor tests a bit and show that they are failling.
Add a Tree printer, cleanups and tests.
Fix wildcard test - should get no answer from empty-non-terminal
Drop the use of dns.RR when in fact the only thing we use is the name
and type of the RR. Cleans up a bunch of stuff and also stops the weird
making of dns.RRs just for a lookup. Should safe some memory as well.
Fixes: #66
