Tweak django tests to skip better
Tweak django tests to skip better

If django isn't installed, we want all the django tests to get skipped.
This fixes an issue with get_es not existing because it doesn't get
imported because django isn't installed.

mozilla/elasticutils,mozilla/elasticutils,einvalentin/elasticutils,einvalentin/elasticutils,einvalentin/elasticutils,mozilla/elasticutils