Adds a Route Handler for Sign Up

This adds a route handler to the tornado app for signup.js. The handler
takes in a company name and password, munges the name into something
that can serve as a viable couchdb database name, and attempts to create
a database of that name. If the database name exists, it throws an
error, which is then returned to the browser for the user to see.

More work needs to be done on the munging as of this point since it is
only rudimentary for testing purposes.