Consistent component documentation

[niallthomson]

Each component should have consistency documentation addressing:

• Nature of the component and its use-cases
• How to build and run the component locally
• Configuration values like environment variables

Components:

• UI
• Cart
• Checkout
• Catalog
• Orders
• Assets

[Ninja4Code]

I tried to update some documentation but it generates a build even though I'm merely updating documentation. There's a lot of syntax errors in some yaml files that seem to have terraform-type syntax in them. I never created those.