Pytest-check-links

- Add Ability to Ignore Link Patterns [30](https://github.com/jupyterlab/pytest-check-links/pull/30) ([afshin](https://github.com/afshin))
- Test with python 3.9 in CI, deal with some windows issues [27](https://github.com/jupyterlab/pytest-check-links/pull/27) ([bollwyvl](https://github.com/bollwyvl))

- Remove defunct Travis CI [24](https://github.com/jupyterlab/pytest-check-links/pull/24) ([afshin](https://github.com/afshin))

- Update for recommended usage of CheckLinks [22](https://github.com/jupyterlab/pytest-check-links/pull/22)

- Another improvement to retry logic [20](https://github.com/jupyterlab/pytest-check-links/pull/20)

- Clean up metadata for dist generation [19](https://github.com/jupyterlab/pytest-check-links/pull/19)
- Improve retry logic and add python 3 classifier [18](https://github.com/jupyterlab/pytest-check-links/pull/18)

- Drop py27 support and add badges [15](https://github.com/jupyterlab/pytest-check-links/pull/15)
- Use requests(-cache) [12](https://github.com/jupyterlab/pytest-check-links/pull/12)
- Add checking of self- and local html anchors [10](https://github.com/jupyterlab/pytest-check-links/pull/10)