Audit Log interface, schema, and cassandra implementation

More audit log stuff.

More audit logging work

Audit log tests and docs
scheduler system test scenarios
test for mutiple policies to execute at the same instance
skipping cron tests
refactor the header validation, setup and using constants
changes fetch url from config for dev and preprod
changes to links test
clean up scripts
changes to server metadata
negative test time.now
updated cloudcafe version
manisht reviews + negative test for update policy type
adding more cooldown validations

clean up within scripts
skip the cron tests
change to create_at_style and unskipped cron tests
Checkpoint supervisor refactor.
Pass authentication function not authenticator class.
Fix lint.
removed at_style now test
Merge branch 'master' into auto-416-scheduler-system-tests