AUI: Add import capability to component anatomy definitions

[bheston]

Pull Request

Description

Allows extracting common definitions shared across multiple components.

Initial example is adding success/error validation across all inputs.

• Can define those styles in one definition file
• Import that file in all input components

Reviewer Notes

The deepmerge package seemed to be the most efficient way to merge the json docs, but open to suggestions.

Test Plan

Tested in AUI pipeline.

Checklist

General

• I have included a change request file using $ npm run change
• I have added tests for my changes.
• I have tested my changes.
• I have updated the project documentation to reflect my changes.
• I have read the CONTRIBUTING documentation for this project.