Make waiting for CloudWatch logs propogation configurable

Thanks for the great helper.

Why is resource deletion so slow? Is that a CloudFormation thing or this tool's peculiarity? I can see in CloudWatch that a deletion of the resource being removed has been successfully completed a couple of minutes ago and there is nothing else in the changeset yet the stack update is in the UPDATE_COMPLETE_CLEANUP_IN_PROGRESS state for a few minutes. I am not using the poll option.

No file, test, or entry point is named. Start by tracing the helper's handling of CloudFormation updates, CloudWatch log propagation, and the non-poll path described in the issue. Done means the waiting period can be configured and the observed deletion workflow honors that setting.

Written by the indexing model from the issue text.