Remove _component suffix from generated files

`rails g ember:component user-info` currently creates these two files:

* `app/components/user-info_component.js.es6`
* `app/templates/components/user-info.hbs`

The es6 file is exported as `app/components/user-info-component`, while the handlebars file remains `components/user-info`. As a result, there are two half-usable components:

* `{{user-info}}` will render the template properly, but will completely ignore the es6 file. In my case, the `didInsertElement` callback was completely ignored, but the contents of the template were displayed.
* `{{user-info-component}}` will properly load the es6 file, but ignore the template. In my case, the `didInsertElement` callback executed, but the template was not rendered.

Renaming the component file to `app/components/user-info.js.es6` allows full use of `{{user-info}}`. So, this pull request removes the `_component` suffix from the generated es6 files.

(An alternative would be renaming the template files to have `-component` on the end, but then you would always have to use the `{{user-info-component ...}}` format).