Verify that nothing links to help.exercism.io

[kytrinyx]

The old help site was deprecated in December 2015. We now have content that is displayed on the main exercism.io website, under each individual language on http://exercism.io/languages.

The content itself is maintained along with the language track itself, under the docs/ directory.

We decided on this approach since the maintainers of each individual language track are in the best position to review documentation about the language itself or the language track on Exercism.

Please verify that nothing in docs/ refers to the help.exercism.io site. It should instead point to http://exercism.io/languages/:track_id (at the moment the various tabs are not linkable, unfortunately, we may need to reorganize the pages in order to fix that).

Also, some language tracks reference help.exercism.io in the SETUP.md file, which gets included into the README of every single exercise in the track.

We may also have referenced non-track-specific content that lived on help.exercism.io. This content has probably been migrated to the Contributing Guide of the x-common repository. If it has not been migrated, it would be a great help if you opened an issue in x-common so that we can remedy the situation. If possible, please link to the old article in the deprecated help repository.

If nothing in this repository references help.exercism.io, then this can safely be closed.

[kytrinyx]

Don't mind me.

I'm adding a reference so we get a visual "todo" list in the top level issue,
https://github.com/exercism/todo/issues/181