Set `therubyracer` as a development dependency
Set `therubyracer` as a development dependency

Execjs should handle the presence of a Javascript runtime, whether it's
Node, therubyracer, or something else. Specifically requiring this
dependency unnecessarily makes this gem heavier

octoberstorm/eslint-rails,octoberstorm/eslint-rails,octoberstorm/eslint-rails,appfolio/eslint-rails,appfolio/eslint-rails,appfolio/eslint-rails