Fetch historical results for a URL from the API

[graphiclunarkid]

We need a mechanism that can query the API for historical results for a URL so that they can be displayed on the website. Perhaps using a back-end PHP script to collect the results via the API and spit them out as JSON, then use JS to display the results in a table.

Issue #29 covers the front-end JS, display and styling. This issue covers the back-end mechanism for interfacing with the API.

[mkillock]

This has been implemented using PHP as a snippet in MODx. Data from API is placed in MODx placeholders, ready for display using custom HTML chunks