Add an `ArcanistCoffeeLintLinter` linter.

Summary:
Add a wrapper around [[http://www.coffeelint.org/ | CoffeeLint]] as an `ArcanistExternalLinter`.

Depends on D9041.

Test Plan: Wrote and executed unit tests.

Reviewers: #blessed_reviewers, epriestley

Reviewed By: #blessed_reviewers, epriestley

Subscribers: epriestley, Korvin

Differential Revision: https://secure.phabricator.com/D9051