Add support for OpenStack Newton and Ocata.

Rework version detection code to just match on major version for
OpenStack projects using semantic versioning.

Provide fallback version detection based on major.minor versions
for swift packages.

Rework config-flags support helpers.

Fix is_ip function to correctly detect both IPv4 and IPv6 addresses.

Change-Id: I04abcebe8181810c4c66e1f0691f5693ce7f7827