Add index.html for viewing the component

Adds an index.html containing the minimum HTML needed to view the
component by itself.
Add scorecard service and module directive

Add the scorecard module direcive from the old solution as well as
a temporary scorecard service based on the old category service.
Require these files in index.js.
Bundle styles from styles module and scorecard styles for build

Add an index.css to the module root that bundles the module's own
styles with the styles from the "styles" module in this module's build
(for testing purposes). Include this bundle in index.html.