docs: Add instructions for local development

[nguyen102]

Issue #, if available:

Description of changes:

• Added instructions and script to allow local development of the code.
• Added instructions and script to allow for packaging of local code and deployment to AWS

Checklist:

• Have you successfully deployed to an AWS account with your changes?

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

[nguyen102]

I tried using yalc links to do local development, but this is a very tedious process. Every time you make a change to a local package:

1. You have to do yalc push to push it to the local package manager.
2. You have to remove all node modules in development package.
3. You then relink the dependent packages in the deployment package.
4. You then do yarn install.

Using yarn links is much faster.