Using /db on origin host to access the store.

Once upon a time the resources (HTML/JS) for the UI were hosted on one web-server, and RESTful/JSON interface hosted on another. We now use NGINX to host both; it servers the static resource itself and proxies /db to the repository.
Fix bug in JSON matcher.

The JSON matcher failed to detect unexpected results. Fixed that. Then some of the tests were failing; fortunately the tests were incorrect rather than the production code. Fixed those too.
Add Spark connector for movies.

I needed to rearrange the build so that the sever and connector could share common code. The connector should use streaming, but Finatra makes that hard. I am exploring alternatives, and will have a fix in a later CL.

closes #48