The specifics of how the authorization for a request is propagated
through the registry app are private implementation details. Hide those
details from outsiders so they can be changed as needed without fear of
breaking third-party code. Move the utilities for attaching a request's
authorization status to its context and retrieving it from the context
into the registry/handlers package as unexported symbols.
Signed-off-by: Cory Snider <csnider@mirantis.com>
868faeec67