no issue
- moved `mobiledoc.renderers.mobiledocHtmlRenderer` to `mobiledoc.mobiledocHtmlRenderer` so that it's easier for the getter to access the parent objects getters
- removed all tests and dependencies that now live in @tryghost/mobiledoc-dom-renderer
- kept the `mobiledocHtmlRenderer` test because that's testing that we've correctly wired up our cards and atoms and the output is what we expect
