Updated runtests.py to support Django 1.8
Updated runtests.py to support Django 1.8

Django 1.6 deprecated DjangoTestSuiteRunner and Django 1.8 dropped it.
Since Django 1.7, if you're running Django in a plain Python script and rely on the DJANGO_SETTINGS_MODULE environment variable, you need to explicitly initialize Django at the beginning using django.setup().

See https://docs.djangoproject.com/en/1.8/releases/1.6/#new-test-runner and https://docs.djangoproject.com/en/1.8/releases/1.7/#standalone-scripts

kajic/django-counter-field