Document new Git-based deployment option

[geerlingguy]

Issue Type

• Documentation Report

Summary

After merging the latest version of the geerlingguy.drupal role to Allow Drupal to be 'deployed' in the VM from Git repositories, we should document how to do this, providing the example of the http://prod.drupalvm.com/ site, the codebase for which resides publicly in this repository: https://github.com/geerlingguy/drupalvm-live

I'd like to specifically add:

• Docs for deploying via git inside the VM alongside the other Deployment docs (docs/deployment.md).
• Adjustments to the production deployment docs assuming you'll use the Git deploy mechanism by default (docs/other/production.md).