Build docs automatically

[spruce]

When a new release is made we should publish the current docs with an automatic tool. Examples are:

• http://usejsdoc.org/
• https://yui.github.io/yuidoc/

[GCorbel]

It would be great. Documentation is definitively not my force.

[spruce]

Even better: https://github.com/ember-learn/ember-cli-addon-docs

[GCorbel]

We have to wait a bit for the stability of the addon but it looks good.