This adds a parse_address(pattern) utility function that returns
(host,port), and uses it wherever where we accept IPv4 and IPv6
addresses and hostnames (or host patterns): the inventory parser
the the add_host action plugin.
It also introduces a more extensive set of unit tests that supersedes
the old add_host unit tests (which didn't actually test add_host, but
only the parsing function).
e.g. db[01:10:3]node-[01:10]
- to do this we split off at the first [...] set, getting the list
of hosts and then repeat until none left.
- also add an optional third parameter which contains the step. (Default: 1)
so range can be [01:10:2] -> 01 03 05 07 09