Updated archetypes to create app.js

TODO:

- [x] Need to update `mojito` version in each archetype to `~0.9`. Current version is set at `0.8` so that the the `mojito create` command can be tested locally since `mojito 0.9.0` is not released yet.
- [x] Update `mojito-cli` documentation to reflect that change
- [ ] Update `mojito-cli` dependency to point to this new version.