Update setup.py
Update setup.py

Moved django requirement to tests_require as it would cause pain for people wanting to upgrade report_builder and not Django. See issue #89
altanawealth/django-report-builder,BrendanBerkley/django-report-builder,AbhiAgarwal/django-report-builder,AbhiAgarwal/django-report-builder,altanawealth/django-report-builder,BrendanBerkley/django-report-builder,altanawealth/django-report-builder,AbhiAgarwal/django-report-builder,BrendanBerkley/django-report-builder