Update code to run under Python3 + Conda packaging
- Updated to work with Python 3 (resources used: 2to3, caniusepython3, pylint, flak8, mypy)
- Added some unit tests to ensure basic functionality of julday
- Updated list of platform specific dependencies to be installed when installing julday in dev mode (see setup.py)
- Installed and tested julday against Python3.[5,6,7,8] using tox
- Formatted Python code to conform to the PEP8 style guide
- Created conda packages for "julday" that can run on Python3.[5,6,7,8]
- Updated .gitlab-ci.yml to run a linter and unit tests for Python3.[5,6,7,8] in GitLab CI pipeline