* sshfp records from nonstandard ports

If port 22 is not open, dns_update.py will not create SSHFP records
because it only scans port 22 for keys. This commit modifies
dns_update.py to parse the sshd_config file for open ports, and
then obtains keys from one of them (even if port 22 is not open).

* modified test of s per JoshData request

* edit CHANGELOG per JoshData

* fix typo