Enable some off-by-default checks
Enable some off-by-default checks

Some of the available checks are disabled by default, like:
[H106] Don’t put vim configuration in source files
[H203] Use assertIs(Not)None to check for None

Change-Id: Icd0162ac6bef12b2303c41bc11c917901c6dcade

openstack/sahara-dashboard,openstack/sahara-dashboard,openstack/sahara-dashboard,openstack/sahara-dashboard