the nsupdate.info zone is configured to allow updating test.nsupdate.info with a non-secret key used for the tests.
we also have a test that tries to update another host with that key and checks that this fails.
change the tests so they only use test.nsupdate.info (if possible).
single-host update secrets need a Domain record for the fqdn of this single host, the fqdn is tried first, before it tries the origin zone.
if a nameserver does not respond, we flag it in the database
(available = False) and stop talking to it for 5 minutes.
after 5 minutes, we flag it available = True again and retry talking to it
(and if not successful, flag it as unavailable again).
this avoids a unresponsive UI as we do a lot of ns queries from the templates
to get v4 and v6 addresses of our hosts from master nameservers.
we log a warning when setting unavailable and a info when setting available.
remove unneeded stuff from settings
(we still need some in conftest.py for the tests, though)
init DB for tests via conftest.py
more update algorithm choices
give origin zone (if we already know it) to dnstools functions
new views: DomainOverview, DeleteDomain
unify deletion templates using delete_object.html
add django-extensions
