Test utilities for repoze.who-powered applications

repoze.who-testutil is a repoze.who plugin which modifies repoze.who‘s
original middleware to make it easier to forge authentication, without
bypassing identification (this is, running the metadata providers).
It’s been created in order to ease testing of repoze.who-powered
applications, in a way independent of the identifiers, authenticators
and challengers used originally by your application, so that you won’t have
to update your test suite as your application grows and the authentication
method changes.