Releasing clldmpg

Do platform test via tox:
```
tox -r
```
Change setup.cfg version to the new version number.
Bump version number:

git commit -a -m"Release <version number>"

Create a release tag:

git tag -a v0.2 -m"first version to be released on pypi"

Release to PyPI

git checkout tags/v$1
python setup.py clean --all
rm dist/*
python -m build -n
twine upload dist/*

Change setup.cfg version to the new version number.
Set version number for next development cycle:
```
git commit -a -m"bumped version number"
```
Push to github:
```
git push origin
git push --tags
```