The auth.basic package was an example of a single implementation
interface that leaked into many different classes. In order to clean
this up, the HttpAuth interface, factories, and Registries all were
removed and the single implementation, BasicAuth, was substituted in all
cases. This removes some dependenies between Auth and the Templates,
which can now use static methods on BasicAuth. BasicAuth was also moved
into the http package and all of the other classes were removed.