Specifically:
- User data is available in all regions, so remove the sentence saying
to check for supported features in each region.
- Clarify domain vs. DNS record resources.
- Explain which DNS record types the `weight`, `port`, and `priority`
arguments are applicable for.
* docs/digitalocean: Adding an import section to the bottom of the DO
importable resources
* docs/azurerm: Adding the Import sections for the AzureRM Importable resources
* docs/aws: Adding the import sections to the AWS provider pages
George Christou