Fix Django version incompatable for Python 3.3

The current required Django version is 1.9.5 which doesn't support
Python 3.3 which causes the Python 3.3 deployment to fail while
using django-ex git repo.

The Django version is modified to use 1.8.x only to include Python
3.3 support.

Signed-off-by: Vu Dinh <vdinh@redhat.com>

requirements.txt

@@ -1,4 +1,4 @@
-Django==1.9.5
+django>=1.8,<1.9
 django-debug-toolbar==1.4
 gunicorn==19.4.5
 psycopg2==2.6.1