Python-hosts

- Promote to 1.0.0 now it is being used in production
- Add support for Python 3.8
- Remove support for Python 3.4 due to dependency PyYAML [dropping support](https://github.com/yaml/pyyaml/issues/281).

- Enable merging of entries
- Remove unnecessary win_inet_pton requirement. Thanks [dotlambda](https://github.com/dotlambda).
- Support adding comments

- Add win_inet_pton to requirements

- Linting

- Freeze win_inet_pton version

- Travis build changes