Initial lodash integration

This is a WIP branch to import [lodash](https://github.com/lodash/lodash-cli) and leverage it's utility functions and performance gains inside Ember.

- [x] Get the ES6 imports working from a build of lodash
- [ ] Use in practice on some test refactors
- [x] Replace current Ember utility functions with lodash functions

Pairing with @crismali on this one at @devmynd studios. Thanks to @jdalton for lodash and helping integrate it in.
`export default function indexOf`