Exceptions and no definitions

I need to change the behat.yml for master using behat 3

- path don't exists (anymore) for testwork. `[Symfony\Component\Config\Definition\Exception\InvalidConfigurationException]   Unrecognized options "paths" under "testwork"`
- extensions names are shortened.

After fixing those is still have an empty --definitions list :-( What is wrong?
Merge pull request #49 from clemens-tolboom/patch-2

Exceptions and no definitions