URL Addressability in Montage Apps

This is related to gh-823 - to support URL addressability and deep linking in Montage applications.

1) To see what an App developer must do, please see /samples/weather/index.html and /samples/sink/index.html. The routes and contextPath etc are defined here.
2) The key changes are in ui/application.js where the URL changes and state changes are tracked and appropriate delegate methods are invoked.

This is an initial implementation of the concept. Any feedback on usage/code is greatly appreciated.