Introduce map-stream / Update readme and dotfiles

* I replaced [event-stream](https://github.com/dominictarr/event-stream) with [map-stream](https://github.com/dominictarr/map-stream), because [es.map()](https://github.com/dominictarr/event-stream#map-asyncfunction) is [just an alias to map-stream](https://github.com/dominictarr/event-stream/blob/480c38d08f5dffa34c41ac737456a3ea98f58d04/index.js#L12).
* I updated .jshintrc. `trailing`, `smarttabs` and `white` options has been removed from JSHint v2.5.0.
* I updated .travis.yml to pass the test on Node v0.8 environment.
* Some readme tweaks