Ember addons that use babel plugins cannot be developed on using `npm link` or `yarn link`

(please let me know if this belongs somewhere else)

When I attempt to work on a ember addon by `yarn link` or `npm link` babel cannot resolve plugins.

Steps to reproduce:
* `ember new`
* git clone a ember addon with babel plugins ( [ember-cli-imgix](https://github.com/imgix/ember-cli-imgix) uses babel plugins ) `git clone git@github.com:imgix/ember-cli-imgix.git`
* run `npm link` in the addons dir.
* run `npm link ` in the newly created ember app.
* run `ember serve`

Observe that ember cannot resolve the babel plugins.

My feeling is that it has something to do with: https://github.com/babel/babel-loader/issues/149#issuecomment-320581223
But I really don't know.

You might see something like:

My current workaround is to push the addon and consume it by commit hash.

---

Output from `ember version --verbose && npm --version && yarn --version`:
```
ember-cli: 3.0.4
http_parser: 2.8.0
node: 8.11.3
v8: 6.2.414.54
uv: 1.19.1
zlib: 1.2.11
ares: 1.10.1-DEV
modules: 57
nghttp2: 1.32.0
napi: 3
openssl: 1.0.2o
icu: 60.1
unicode: 10.0
cldr: 32.0
tz: 2017c
os: darwin x64
5.6.0
1.7.0
```