Remove comment about client_instance script

The script attribute of a client_instance is tested in the view,
for example in body-end.html:

    <% if (model.get('script')) { %>

It can be set to false to disable including of our rather large
JavaScript assets.
Remove query params when using Stagecraft API

When we pass a path onto Stagecraft to find out information about
a dashboard, we don't want to include any query parameters because
this will cause Stagecraft to return a 404.
Merge pull request #816 from alphagov/79950942-bugfix-cachebusting-stagecraft

Remove query params when using Stagecraft API