Support Cloudwatch Event types for event-info #231
Description
Cloud custodian uses Cloudwatch Events to trigger Lambda executions. It would be fantastic to support this event type.
https://docs.aws.amazon.com/AmazonCloudWatch/latest/events/CloudWatchEventsandEventPatterns.html
https://docs.aws.amazon.com/AmazonCloudWatch/latest/events/EventTypes.html