Update ArcanistCoffeeLintLinter to be compatible with CoffeeLint v1.4.0.

Summary: CoffeeLint v1.4.0 deprecated the --checkstyle flag in favor of --reporter=checkstyle.

Test Plan: arc unit

Reviewers: epriestley, Blessed Reviewers

Reviewed By: epriestley, Blessed Reviewers

Subscribers: epriestley, Korvin

Differential Revision: https://secure.phabricator.com/D9181