Enabled psycopg2 2.6

setup.py

@@ -112,7 +112,7 @@ install_requires = [
     'mock>=0.8.0,<1.1',
     'petname>=1.7,<1.8',
     'progressbar>=2.2,<2.4',
-    'psycopg2>=2.5.0,<2.6.0',
+    'psycopg2>=2.5.0,<2.7.0',
     'pytest>=2.6.4,<2.7.0',
     'pytest-django>=2.9.1,<2.10.0',
     'python-dateutil>=2.0.0,<3.0.0',