Contributing to clldutils

Installing clldutils for development

Fork clld/clldutils
Clone your fork
Change into the top-level directory of the clone
Install clldutils for development (preferably in a separate virtual environment) running
```
pip install -r requirements.txt
```
Make sure the test suite passes:
```
pytest
```
Optionally make sure tests pass on all supported platforms:
```
tox -r
```