Improvement for all ec2_* modules: support aws tagging

I would like to add tagging capability to all ec2_* modules a la ec2’s ‘instance_tags’ so I don’t have to setup another task just to invoke ec2_tag module after every ec2 instance I provision.

In some cases, such as volumes, subnets, routes, etc, I would like for for child resources to inherit tags from their parents. For example, when adding a volume to an instance tagged “environment=this”, “billing_code=that”, volume should inherit the two tags from its instance.

-Alex