[chore] Update Version of Node

[pamo]

Description

When I try to run the app locally I get this error when running gulp

events.js:154
      throw er; // Unhandled 'error' event
      ^
TypeError: this is not a typed array.
    at Function.from (native)
    at /Users/pamo/Development/funretro/node_modules/gulp-autoprefixer/index.js:25:27
    at run (/Users/pamo/Development/funretro/node_modules/core-js/modules/es6.promise.js:66:22)
    at /Users/pamo/Development/funretro/node_modules/core-js/modules/es6.promise.js:79:30
    at flush (/Users/pamo/Development/funretro/node_modules/core-js/modules/_microtask.js:18:9)
    at nextTickCallbackWith0Args (node.js:453:9)
    at process._tickCallback (node.js:382:13)

Motivation

This seems to be an issue with versions of Node < 6 sindresorhus/gulp-autoprefixer#83

Updating the project version of node would benefit future development since Node 5 no longer has long-term support and introduce features released as a part of npm 5 to the project.