Add a new plugin file(scripts/lab.js).

Add plugins 'lab.hackernews(lab.hn)' and 'lab.echo' in lab.js

The clojurescript source code is permanently maintained on
https://github.com/Sorrow17/hubot-lab-plugin/tree/master/hubot-lab-plugin/
Merge pull request #9 from Sorrow17/lab.js

Lab.js plugin