Test cases files

[shmuga]

Thanks for such a nice cli! I find it very helpful.

This is a feature request that could be useful: a test case files. The way I see it is when someone starts to edit any problem - the test cases file is created. That test file is pre-populated with all examples from the problem and could be extended with some custom test cases.

During the test run of the problem if nothing is specified all test cases from the file would be picked up.
This feature does not require any new API for the CLI and fully backwards compatible.

Any thoughts on this?