Refactor Stacks to follow standard

[igorlg]

Description of changes:

• Refactored each Macro stack to follow a standard in Lambda Function setup and naming convention
• Added Makefile to simplify deploying stacks
• Added a "master" stack at the root of the repository to deploy all macros as nested stacks
• Standardized all Lambda runtimes as Python3.9 (as Python <= 3.6 is EOL)
• Minor fixes and adjustments

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.

[ericzbeard]

We are archiving this repository in favor of similar content located here: https://github.com/aws-cloudformation/aws-cloudformation-templates/tree/main/aws/services/CloudFormation/MacrosExamples