Abstract Addon logic for tree generation.

* Expose `Addon.prototype.isDevelopingAddon` function.
* Expose `Addon.prototype.treeGenerator` function, that automatically
  handles the returning an `unwatchedTree` vs the bare directory
  (therefore causing it to be watched).
Correct npm dependency order

Fixed order since npm sorts dependencies alphabetically after `npm install`.
Merge pull request #1785 from rwjblue/easier-overriding-addon-trees

Abstract Addon logic for tree generation.
Merge pull request #1786 from quaertym/patch-12

Correct npm dependency order
bump ember-cli-qunit version
Fix incorrect npm loglevel with --verbose flag

https://www.npmjs.org/doc/misc/npm-config.html
Merge pull request #1787 from sandstrom/patch-1

Fix incorrect npm loglevel with --verbose flag
Merge pull request #1770 from jakecraige/patch-6

Update ember-cli-qunit version
Update broccoli-caching-writer dependents to allow linking fallback.

* Update broccoli-caching-writer to handle fallbacks if linking is not
  possible (for example in a vagrant box).
* Update broccoli-file-mover
* Update broccoli-file-remover
Silent analytics

Now, there is a way to disable analytics using `.ember-cli` settings
file by adding:

```json
{
  "disableAnalytics": false
}
```
Merge pull request #1797 from twokul/silent-mode

Silent analytics
Merge pull request #1799 from rwjblue/update-to-enable-vagrant

Update broccoli-caching-writer dependents to allow linking fallback.
Update RELEASE.md
alphabetize
manually dedupe by hoisting to parent package.json
Opt out of bower analytics, to avoid prompt
Merge pull request #1805 from sandstrom/patch-1

Avoid issue where `ember init` stalls on fresh system
Update `core-object` with ignored `tests` folder
Merge pull request #1806 from twokul/new-core-object

Update `core-object` with ignored `tests` folder
Merge pull request #1803 from stefanpenner/dedupe

Dedupe