Partial commit. Starts to separate model from controllers, and add CORS support (initially insecurely)

This is part of a move to experiment with separating the Angularjs client into its own project with a build system more typical for front-end projects.
Partial commit. Remove the UI, as it is served by redirection to a "static app"
Partial commit. GroupCrit and OutputCrit are replaced by Critique

Critiques now have a "target", and a target strategy.