Previously only bottom half was being executed. This was caused by
duplicate keys. I've moved postinstall to a script.

BREAKING CHANGE: Now node 4 is required to build the project. This is
because protractor 3 requires is. I decided to make the switch now,
because it would happen anyway at some point.

This change makes it possible to run tests, integration tests and lint
on Travis CI. It also prepares a special Gulp task to perform the same
activities locally. This is handy when, e.g., sending a pull requrest.

The Godep tool is de facto standard in the Go and Kubernetes
communities. So, the ealier this project switches to it, the better. The
setup uses recommended layout from the project docs:
https://github.com/tools/godep

You might wonder why to pull entire Godeps folder here. This is how
Godeps strongly advise to do.

- Caches the installed Bower dependencies for faster builds.
- Removes global Node.JS modules gulp and bower from travis conf & make
	them devDependencies for more reproducable and faster builds.

This sets the option in the Travis CI configuration to cache all the
downloaded Node.JS modules, which can senificantly speed up travis
builds.

This is a basic config that builds the project. Later, more rules will
be added.