Configure clouldwatch metrics for WBTransactor

[mgrbyte]

The cloudformation configured Datomic transactor would benefit from enabling cloudwatch metrics.

These metrics are usually written to $DATOMIC_HOME/log/%Y-%m-%d.log.
e.g if events omitted with Alarm.* should be looked at immediately.

This is more useful for the build transactor, since it's more likely to have "interesting" metrics during the import, but as more is done with the website, then it'll probably useful to configure them for the website transactor too.

Requirements for enabling:

• Attaching two policies to the IAM transactor role (either manually in the IAM console for the role or preferably with a cli script).

See section "Using S3 log storage and CloudWatch metrics" about adding the two policies.