Adding Provider Source to HashiCorp Terraform

Recently, we announced that we will be adding Terraform providers to the Registry. We've started with HashiCorp maintained providers and are working to include all Terraform providers. Soon, Terraform will be able to automatically download and install all providers published in the Registry, including community providers. While the installation process for HashiCorp maintained providers isn't changing, the configuration language is getting an update to support the eventual inclusion of partner and community providers in the Terraform Registry.