update the encrypt (save) and decrypt functions to be python3/dnspython friendly
using bytestrings instead of expecting strings.
statistic_port is now control_port.
removed the validations from admin.py because the model fields now provide
for validators of their data.
add creds dir to the settings.py
While it might not be that common to have a DNS server listening on a
non-standard port for DNS queries, it's also useful for local testing.
I used the opportunity to add model migrations as well to enable smooth model
upgrades.
jeffrey forman
Daniel Roschka
Jeffrey Forman