Often you want to create components that can be added to a class
arbitrarily. This module makes it easy for the end user to use these
components. Instead of requiring the user to create a named class with the
desired roles applied, or applying roles to the instance one-by-one, he can
just pass a 'traits' parameter to the class's 'new_with_traits'
constructor. This role will then apply the roles in one go, cache the
resulting class (for efficiency), and return a new instance. Arguments
meant to initialize the applied roles' attributes can also be passed to the
constructor.