update minimum django version

Author: nikolas

setup.py

@@ -11,7 +11,7 @@
     url="https://github.com/ccnmtl/django-smoketest",
     description="Django smoketest framework",
     long_description=open(os.path.join(ROOT, 'README.md')).read(),
-    install_requires=['Django>=1.6', 'nose'],
+    install_requires=['Django>=1.8', 'nose'],
     scripts=[],
     license="BSD",
     platforms=["any"],