Refresh including django, python and requirements

Closes #6

See merge request uis/devops/raven/ucamwebauth-2-oauth2!4

Use uis-master ucam-wls branch

See merge request uis/devops/raven/ucamwebauth-2-oauth2!3

also fix bad registry reference in testclient

Add an initial implementation

Closes #1

See merge request uis/devops/raven/ucamwebauth-2-oauth2!2

Add a basic implementation of a WebAuth to OAuth2 shim. The common iact,
params and fail query flags are respected.

We make use of the ucam_wls library to provide the server implementation
and glue it together in a single Django view.

As well as unit tests, manual integration testing is possible by
visiting http://localhost:8001 in the browser with the development or
production environments running. This provides a simple server using
mod_ucamwebauth to test authentication.

Closes #1

We make use of ucamwebauth for running tests as it has an (independent)
implementation of the validation-side of the WLS flow.

Running ./tox.sh -e py3 did not result in only the Python tests being
run because arguments were not being passed to tox.

Add initial boilerplate

Closes #4

See merge request uis/devops/raven/ucamwebauth-2-oauth2!1

Remove the api and ui as this webapp will have no UI of its own; it is
just an intermediary between different authentication mechanisms.

Fix up the Docker file and development infrastructure so that the
frontend is not built.