Add a new_renderTiddler() method for testing
Rig up a temporary browser rendering of the new widget mechanism

At this point the rendering fails because of missing widgets
Add className property support for fakedom elements
Add a message for undefined widgets
More work on the list widget
Add a rendertiddler command based on the new widget mechanism

Lets us run `nbld.sh` to attempt to build an index.html
More widgets
More tests