- Add this option so command line arguments can be supplied to hadolint
- This will be respected when running in docker and via the executable
- Preserve the --no-color and - flags, and add these to the list
- Add to docs and tests
* Add documentation for hadolint (doc/ale-hadolint.txt)
* Allow `hadolint` linter to run via docker image
These changes enable the `hadolint` linter to run via the author's
docker image, if present. Three modes are supported:
* never use docker;
* always use docker; and
* use docker as a failback.