Update version of ember-cli-eslint used in new applications.

[rwjblue]

New applications will now get ember-cli-eslint@3 which uses the latest version of eslint (we previously could not do this update due to eslint@3 dropping support for Node 0.12).

[rwjblue]

@homu r+

[homu]

📌 Commit d09f10e has been approved by rwjblue

[homu]

⚡ Test exempted - status

[nathanhammond]

Given more time to think about it, I'm not 100% happy with how ember-cli-eslint isn't in the default blueprint anymore. Many users don't use ember init to handle upgrades which means that they end up "stuck" on whichever version they have installed, or worse, delete it without paying attention as to why when they view the comparison.

This whole setup exists for one reason: we need to be able to run all default blueprints for bundled addons once per application creation. We possibly want to run the default blueprint for every addon in the application each time that addon gets updated. But we can't run that blueprint unless we actually have a node_modules folder. This complicates programmatic fixture creation as well.

/cc @Turbo87

[Turbo87]

@nathanhammond I'm open to other suggestions...