In this changeset, I updated the 'goal_id' field into the AuditTemplate
to now become a mandatory foreign key towards the Goal model. I also
added the 'strategy_id' field into the AuditTemplate model to be an
optional foreign key onto the Strategy model.
This changeset also includes an update of the /audit_template
Watcher API endpoint to reflect the previous changes.
As this changeset changes the API, this should be merged alongside the
related changeset from python-watcherclient.
Partially Implements: blueprint get-goal-from-strategy
Change-Id: Ic0573d036d1bbd7820f8eb963e47912d6b3ed1a9
2966b93777