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* Extra template validation (635)
* Update ECS to Jan 17, 2017 release (642)
* Add Timezone property to DBInstance (643)
* Test Python 3.6 (644)
* Adding RDS engine support for oracle*se2 (646)
* Correct required in ecs.Service (645)
* Add Separator property to IoT Firehose Action
* Add Fn::Split function (647)
* Added to_dict() method to troposphere.Template (651)
* Allow use of AWSHelperFn for IOPS (652)
* Allow HelperFN w/ autoscaling policies (654)