chore(package): update eslint to version 2.13.1
chore(package): update eslint to version 2.13.1

https://greenkeeper.io/
mozilla/web-ext,shubheksha/web-ext,rpl/web-ext,mozilla/web-ext,kumar303/web-ext,rpl/web-ext,kumar303/web-ext,shubheksha/web-ext