Add sync coming soon status from LYS to WPCOM

Closes #1496

Sync coming soon status from LYS to WPCOM.

When updating to either Live or Coming soon in Settings > WooCommerce > Site visibility
When clicking on Launch in Launch your store task

Note: This PR requires D159271-code

Patch your wpcom sandbox with D159271-code
SSH to your atomic site
Run vim ~/htdocs/wp-config.php
Add the line near the top of the config define( 'JETPACK__SANDBOX_DOMAIN', 'SANDBOX_URL' ); - Replace SANDBOX_URL with your sandbox URL and save
Refresh wp-admin page and observe Jetpack API Sandboxed on admin bar

SSH into your sandbox
Run php ./public_html/bin/atomic/unlaunch-site.php SITE_URL - Replace SITE_URL with your atomic site URL

Use a WPCOM atomic e-commerce site
Enable LYS feature flag (via beta tester or you can remove these lines).
Go to Settings > WooCommerce > Site visibility
Ensure Coming soon is selected
Go to https://wordpress.com/settings/general/SITE_URL
Ensure your site is not launched yet. If not, do the steps in instructions above this one
Go to My Home
Click on Launch your store task
Click on Launch your store button
Go to https://wordpress.com/settings/general/SITE_URL
Observe your site is live

[ ] Have you added an explanation of what your changes do and why you'd like us to include them?
[ ] Have you written new tests for your changes, as applicable?

[ ] I have reviewed that everything is sanitized/escaped appropriately for any SQL or XSS injection possibilities. I made sure Linting is not ignored or disabled.

Automattic / wc-calypso-bridge