Set working version of node docker image

[nsteenv]

Fix error when running docker build command with node 0.12-onbuild version:

Status: Downloaded newer image for node:0.12-onbuild
Executing 3 build triggers
Trigger 0, COPY package.json /usr/src/app/
Step 0 : COPY package.json /usr/src/app/
Trigger 1, RUN npm install
Step 0 : RUN npm install
---> Running in bae4737c1e9d
npm WARN deprecated [email protected]: use gulp-rimraf instead
npm WARN peerDependencies The peer dependency bower@^1.x included from bower-requirejs will >no
npm WARN peerDependencies longer be automatically installed to fulfill the peerDependency
npm WARN peerDependencies in npm 3+. Your application will need to depend on it explicitly.
<npm WARN prefer global [email protected] should be installed with -g
npm ERR! Linux 3.13.0-29-generic
npm ERR! argv "node" "/usr/local/bin/npm" "install"
npm ERR! node v0.12.7
npm ERR! npm v2.11.3

npm ERR! shasum check failed for /tmp/npm-5-e023de54/registry.npmjs.org/jshint/-/jshint-2.8.0.tgz
npm ERR! Expected: 1d09a3bd913c4cadfa81bf18d582bd85bffe0d44
npm ERR! Actual: f599a4ca65030850b8b9737f3db59c5386f0ab20
npm ERR! From: https://registry.npmjs.org/jshint/-/jshint-2.8.0.tgz
npm ERR!
npm ERR! If you need help, you may report this error at:
npm ERR! https://github.com/npm/npm/issues

npm ERR! Please include the following file with any support request:
npm ERR! /usr/src/app/npm-debug.log
The command '/bin/sh -c npm install' returned a non-zero code: 1