This bunch of if...elif...fi is there to reproduce the way the
resource_group and nodename are currently built in the azure infra.

So that we can use those script instead of clicking in the portal ui.

We will either need to:

- factorize that snippet part at some point (which is duplicated in
  add-disk, create-vm and here so far)

- rename our resources in the azure portal

In regards to resource group, vm name computations.

Ideally, this should be factorized.

That'll avoid T1128 reiterating in the future...

[1] https://docs.microsoft.com/en-us/azure/virtual-machines/linux/expand-disks

Related T1094

We need that version because our manifests need it.
If not, the provisioning fails at the puppet run step.

According to our current azure dashboard

Summary:
- Add comments
- Drop what's not needed
- Need to test it still works though

Summary:
- Add comments
- Drop what's unused
- Migrate from azure (npm cli) from az (somewhat debian packaged [1])

[1] https://docs.microsoft.com/en-us/cli/azure/install-azure-cli-apt?view=azure-cli-latest