Add description arg to JSONSchemaTypeHelper `Property` class

• Add support for JSON Schema Property.description as optional str input.
• Update cookiecutters with sample implementations
• Verify that description prints to STDOUT when running --about --format=json
• Verify that description prints in the catalog running --discover

The goal of this will be to automate a more meaningful version of settings discovery, for use in the Hub. Side benefit is the ability to add machine-readable descriptors directly into catalog metadata.

We may also use this information in a future --about --format=md to print copy-paste-able text to inject into a repo's readme.