Changes necessary for Django 1.11 tests to start

- Certificates management commands updates
- Moving reverse calls in tests into setUp from class definition
- Import shuffling
- Consolidating cryptograhpy version to 1.9

requirements/edx/base.txt

@@ -11,7 +11,7 @@ bleach==1.4
 html5lib==0.999
 boto==2.39.0
 celery==3.1.18
-cryptography==1.5.3
+cryptography==1.9
 cssselect==0.9.1
 dealer==2.0.4
 defusedxml==0.4.1