Allow JX to be redefined for NodeJS files
Summary: This silences a bunch of JSHint warnings.
Test Plan: arc lint -- support/aphlict/server/lib/AphlictLog.js
Reviewers: epriestley, Blessed Reviewers
Reviewed By: epriestley, Blessed Reviewers
Subscribers: Korvin, epriestley
Differential Revision: https://secure.phabricator.com/D11084