Fixing ipaddr requirement

[kfreezen]

Two changes:

1. python >= 3.6.1 -- poetry install did not like pre-commit = "2.16.0"
2. Changed ipaddress back to ipaddr and added a python <3.3 to avoid installing ipaddr on python versions 3.3 and above.

The code seems to already handle ipaddress/ipaddr shift in code already, so change number 2 should be fine from a code perspective.

[kido5217]

According to my experience, general python dependency should be specified without patch version, or pypi will not mark package as 3.6 compatible, only as 3.7+
Specific python version for pre-commit should be listed for pre-commit only:

pre-commit = {version = "2.16.0", python = "^3.6.1"}

[mpenning]

Thank you for your PR, but this PR doesn't do what we want now... we don't want to deal with anything related to ipaddr at this point