* update to Django 1.11.5
* explicitly list all dependencies so we can `pip install --no-deps`
* layout and config fixes from deployment tests

* subscriptions: renewals are now monitored
* ux: "Yes" or "No" for is active (not "True" and "False")
* ux: only display download links for active services
* admin: improve admin page readability (ids and smart column values)

* this is so very first credit doesn't appear short (29 days rather than 30)
* also added DEBUG flag to skip activation command when activation is not being tested (e.g. when developing/testing on localhost)

* include links to code
* clean up README, COPYING and associated files

* force lowercase usernames
* FIXME: can still start username with a numeral and include non-alphanumerics

* uses new SITE_DOMAIN value
* replace WOO1_EMAIL_SUFFIX with SITE_DOMAIN
* use user_identity when generating ovpn certificates

* parameterised variable for file location
* link to instructions PDF
* SITE_DOMAIN is part of user identity

* add rabbitmq and ssh/openvpn instructions to README
* correct celery worker/beat invocation
* add error_message to limitmonitor.external_credit (store the message when a credit attempt fails)
* warning but allow missing host key (ssh connection to openvpn server)
* syntax and other minor fixes

* define deactivation task

* refine schema for limitmonitor
* clean up html templates
* move global admin settings from app to urls.py

* clean up ldapregister templates
* mention external resources in README

* also tweak README URL and homepage links

* move admin link to correct location
* admin link only appears for superusers
* tweak home page to use site title rather than Purist
* tweak home page to match current website standin