Use simplified URLs for promulgated bundles.

Avoid showing the user part in the bundle URLs
displayed in the bundle browser view header and
in quickstart instructions.

Also moved the bundle location above the deployment
stats in the header, so that the URL is not hidden
by the "Deploy this bundle" button.

QA:
- make devel/debug/prod;
- search for bundles and pick a promulgated one;
- check the simplified bundle URL is showed in the header
  and in the quickstart howto (Deploy tab);
- now pick a non-promulgated bundle: this time the user
  is properly included in the URL.