Use map-stream instead of event-stream

https://github.com/dominictarr/map-stream
Update lodash, chai, mocha and gulp
Remove Node versions Travis CI doesn't support

http://docs.travis-ci.com/user/languages/javascript-with-nodejs/#Provide
d-Node.js-Versions
Merge pull request #5 from shinnn/map-stream

Use map-stream instead of event-stream / Fix .travis.yml