add ecs property validation

[jhsinger-klotho]

	* creating ECS Task Definition (ecs_service_0): ClientException: When networkMode=awsvpc, the host ports and container ports in port mappings must match.
	* creating ECS Task Definition (ecs_service_0): ClientException: Invalid setting for container 'ecs_service_0'. At least one of 'memory' or 'memoryReservation' must be specified. (I believe this matters when you have multiple containers
	* creating ECS Task Definition (ecs_service_0): ClientException: Log driver awslogs requires options: awslogs-region, awslogs-group
	* creating ECS Task Definition (ecs_service_0): ClientException: A dependency container with SUCCESS or COMPLETE condition cannot be an essential container
	* creating ECS Task Definition (ecs_service_0): ClientException: Fargate requires that 'cpu' be defined at the task level.
	* creating ECS Task Definition (ecs_service_0): ClientException: The sum of all container 'cpu' values cannot be greater than the value of the task 'cpu'.