chore(package): update coveralls to version 2.11.9
chore(package): update coveralls to version 2.11.9

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