Add StreamController, views and presenter + refactor project level view
and presenter to use these.
ProjectPresenter uses composition rather than inheriting from StreamPresenter
Refactor makes stream name and stories members of StreamPresenter
Add poltergeist for js feature testing
Use database cleaner to truncate when running js features
Load each of a project's streams asynchronously
Fix project page not working correctly due to turbolinks not invoking JS $(document).ready