Add some more documentation

Author: atodorov

README.rst

@@ -15,4 +15,36 @@ TODO:
 - package this backend and publish to PyPI
 - enable testing
 - why there are 2 classes for kerberos backend? which one if the real deal
+  maybe 'tcms.auth.kerberos.ModAuthKerbBackend' ????
 - check-out https://github.com/kiwitcms/Kiwi/issues/240
+
+
+This package provides passwordless authentication for Kiwi TCMS via Kerberos.
+This is turned off by default because most organizations do not use it. To enable
+configure the following settings::
+
+    MIDDLEWARE += [
+        'django.contrib.auth.middleware.RemoteUserMiddleware',
+    ]
+
+    AUTHENTICATION_BACKENDS += [
+        'tcms.auth.kerberos.ModAuthKerbBackend',
+    ]
+
+    KRB5_REALM='YOUR-DOMAIN.COM'
+
+
+Also modify Kiwi TCMS ``Dockerfile`` to include the following lines::
+
+    RUN yum -y install krb5-devel mod_auth_kerb
+    RUN pip install kerberos
+    COPY ./auth_kerb.conf /etc/httpd/conf.d/
+
+Where ``auth_kerb.conf`` is your Kerberos configuration file for Apache!
+More information about it can be found
+`here <https://access.redhat.com/documentation/en-US/Red_Hat_JBoss_Web_Server/2/html/HTTP_Connectors_Load_Balancing_Guide/ch10s02s03.html>`_.
+
+.. warning::
+
+    Unless Kerberos authentication is configured and fully-operational the
+    XML-RPC method `Auth.login_krbv()` will not work!