WIP moving new project form to own Angular app

The new project form is LanguageForge-specific, so it doesn't belong in
the bellows/projects app. We'll move it to its own app, which has the
added advantage that we can use the Angular-UI $state functions to make
a nice-looking progress wizard (just as with the bellows/signup app).

This commit lays out the framework for the New Project wizard, which
will be fleshed out in subsequent commits.
WIP on new project form: add validation messages

Add a placeholder for form validation messages. This will allow us to
communicate to the user "Here's why you couldn't click on the Forward
button" without disabling the button, and will also provide a good place
for positive feedback when the form is valid and ready to advance.
WIP on new project form: copy over old HTML

The HTML from the "Create New Project" form in the bellows/projects app
is a good starting point for creating the LanguageForge-specific new
project form. It's still a bit ugly, but it won't need too much cleaning
up in order to turn it into something solid.