Create 0006_object_pk_index.py
Create 0006_object_pk_index.py

Seq Scan on auditlog_logentry on heroku postgres. I suspect because of missing index.

````
SELECT "auditlog_logentry"."id", "auditlog_logentry"."content_type_id", "auditlog_logentry"."object_pk", "auditlog_logentry"."object_id", "auditlog_logentry"."object_repr", "auditlog_logentry"."action", "auditlog_logentry"."changes", "auditlog_logentry"."actor_id", "auditlog_logentry"."remote_addr", "auditlog_logentry"."timestamp", "auditlog_logentry"."additional_data" FROM "auditlog_logentry" WHERE ("auditlog_logentry"."content_type_id" = %s AND "auditlog_logentry"."object_pk" = %s) 
```
kbussell/django-auditlog,jjkester/django-auditlog,Zmeylol/auditlog,chris-griffin/django-auditlog