Terraform CLI create only container for backend if storage account exists - IMPROVEMENT

[akordowski]

The Terraform CLI init command contains the Create Backend (If not exists) option. When set to true the Azure CLI tries to create a Resource Group and a Storage Account with a Container. But if the Storage Account already exists the command fails. It would be a great improvement if the container is created when the Storage Account already exists.

An other improvement would be also a option to set the verbosity level for the Azure CLI, when running the Create Backend command.