Hi, first of all thanks for the great project!
When running tox from my bootstrapped project, I have the following warning that gets printed:
warning: Check: This command has been deprecated. Use twine check instead: https://packaging.python.org/guides/making-a-pypi-friendly-readme#validating-restructuredtext-markup

Its not a big deal but I thought it was worth to be fixed, I'll push a PR shortly