Make pending meta/list test live
Refactor regressions.t.js to use Mocha/Chai
Refactor features.t.js to use Mocha/Chai
Refactor interface.t.js to use Mocha/Chai
Use a single HTML test file for regressions & interface
Fix leaking variable
Hack together feature tests in browser.

The tests look at all the files in the directories and run all the text/json
pairs so they need a web server to serve directory listings, and so everything
needs to be served by it to avoid cross-domain XHR.