Addition of shipping address to Checkout POC

[ericerway]

This issue is for the following packages:

[X] venia-concept
[ ] pwa-buildpack
[ ] peregrine
[ ] pwa-module
[ ] pwa-devdocs

This issue is a:

[ ] Bug
[X] Feature suggestion
[ ] Documentation issue
[ ] Other (Please Specify)

Environment

Question	Answer
Magento version
Operating System + version
node.js version (node -v)
npm version (npm -v)

Description

As a shopper I want to add or modify a shipping address (unauthenticated) to Checkout experience in Venia so that I can complete a purchase with my actual address.

==Edit and validation; dependency on field components

// Scenario: add shipping address

**Independent of PaymentRequest research

Expected result:

Updated version of Checkout POC with add/edit shipping address
Testing and documentation (as appropriate)

Possible solutions: