Include relative URL root in JS setting Teaspoon.root if present.

Currently we can use Teaspoon in application deployed under custom context root (see #133) - let's say **http://localhost:3000/some-app/teaspoon/default**. However when I want to return from filtered specs, using 'Remove' link - it returns to **http://localhost:3000/teaspoon/default**, which is wrong.

Simplest solution is to alter ``Teaspoon.root`` in the template.

What do you think? Any idea at which level this should be tested?