Add a "template" parameter to the template tags
Make it possible to pass a template filename as input parameter to the "render_form", "render_field" and "render_label" template tags. And/or make it possible to dynamically add a "template directory" where to search for templates.
With this enhancement, it will be possible for a template designer to use a "one shot" specific template for a given form (or form element).
This will also simplify the ouput test described in issue
#1, since it will be possible, in tests, to use formrenderingtools builtin templates rather than project's ones.