Display order-status link in order-placed email, for logged-in users

Upgrade to Bootstrap 3.4

Update pillow to 5.4.1

Update pycountry to 18.12.8

-Added help messages for all targets
-Added help target
-Divided targets into blocks for easy understanding
-Added new target install-js for npm install
-Used new target in install and css
-divided install target into 3 targets
    install-python
    install-test
    install-js
-Updated i18n traget names
-Added install-migrations-testing-requirements target
-Used install-migrations-testing-requirements in test_migrations
-Updated .PHONY

Remove unused get_class import from catalogue/abstract_models.py

Properly populate user instance passed to password validators

Update pillow to 5.4.0

Update pymysql to 0.9.3

Update django-debug-toolbar to 1.11

Update requests to 2.21.0

Update test dependencies

Merge Oscar and Django app configs

Update ipython to 7.2.0

Added functionality to check if a voucher is available for basket

Add functionality to check if a voucher is
available for a basket or not.

Update django-extensions to 2.1.4

Update whitenoise to 4.1.2

Update django-redis to 4.10.0

Also refactor catalogue option group and option tests.

Added indexes on fields that are used in every query.

Update whitenoise to 4.1.1

Update psycopg2 to 2.7.6.1

Update requests to 2.20.1