Add pytest
Make Circle run py.test
Fixed pytest-django requirement pinning
Allow db access for some tests
Merge pull request #50 from macro1/pytest

Fix pytest-django pinning and allow some DB access
Remove unused pytest import
Use simple asserts because pytest is awesome
Merge branch 'pytest'

Conflicts:
	django/dev-requirements.txt
	django/similarities/tests/test_utils.py
	django/users/tests/test_models.py