Issue #3108 -- Preliminary commit:

There is a dependency on Underscore.js

This file has been modified just for demonstration purposes to allow the tests to work.

Modification done according to this other pull request for Underscore.js:

https://github.com/jashkenas/underscore/pull/1100
Issue #3108 -- Allow proxying of options to 'url(...)' via 'fetch(...)'.