No longer supported by upstream.

After 615a59a5, you need to use
specifiers to install all of the dependencies. Use the all specifier in
tests.

Now it runs the CLI as well. Duplicates other jobs but should be easier
to debug some cases.

- Fix missing output of bats in CI.
- Output doctests to junit only in CI.

- Use templates.
- junit output for doctest and bats.

Shouldn't have beem merged this way.

Also:

- Update the README.
- Test more environments (every supported CPythong and PyPy version and
CPython 2.7).