Fixes DEVELOPER-748

I think, anyway. Local testing is inconclusive.

Adding DCP changes and using it in the javascript

I completely forgot about this (the dcp part). We need this added to the
environments to make use of this.

Adding the sandbox quickstarts to be experimental too.

Removing include_in_all
Cleanup a bit of the site config
DEVELOPER-922 Removed all site.context_url links
DEVELOPER-922 Fixed invalid following slashes
Update cdn.yml
Updated Gemfile.lock
DEVELOPER-928 Update the homepage hero to anounce JUDCon:Brazil CFP
Merge pull request #471 from pmuir/cleanup

Cleanup a bit of the site config
Update cdn.yml
Merge pull request #473 from paulrobinson/DEVELOPER-928

Developer 928
smoother buzz infinite scrolling. Fixes DEVELOPER-888
Update cdn.yml
Fixing doubple highlight between keyboard and mouse mixed use. DEVELOPER-495
DEVELOPER-929 only copy files if they exist
DEVELOPER-931 Typo in “São Paulo” hero
books loading indicator and error state. Fixes DEVELOPER-787
Merge pull request #478 from paulrobinson/DEVELOPER-931

DEVELOPER-931 Typo in “São Paulo” hero
Update cdn.yml
Merge pull request #479 from wesbos/DEVELOPER-767

books loading indicator and error state. Fixes DEVELOPER-787
Merge pull request #475 from wesbos/DEVELOPER-495

Fixing double highlight between keyboard and mouse mixed use. DEVELOPER-495