Add additional v3 vm sizes permitted for dcos master and agent

[yakman2020]

Current DCOS templates are not allowed to use the VM sizes like D2s_v3. We very much need those.

Which issue this PR fixes (optional, in fixes #<issue number>(, fixes #<issue_number>, ...) format, will close that issue when PR gets merged): fixes #

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Release note:

[jackfrancis]

@yakman2020 These const values are auto-generated, so we'll have to update the script at pkg/acsengine/Get-AzureConstants.py. The reason why Standard_D2s_v3 isn't available is because the resourceDiskSizeInMb value for that SKU doesn't meet the minimum requirement defined in the script above. Here's the output for that SKU from az vm list-sizes -l eastus (using eastus as an example):

{
    "maxDataDiskCount": 4,
    "memoryInMb": 8192,
    "name": "Standard_D2s_v3",
    "numberOfCores": 2,
    "osDiskSizeInMb": 1047552,
    "resourceDiskSizeInMb": 16384
  },

Do we want to to decrease the value of this constant here?:

https://github.com/Azure/acs-engine/blob/master/pkg/acsengine/Get-AzureConstants.py#L23

(That will inevitably bring in a bunch more master SKU sizes into the whitelist, I assume that's O.K.)

[yakman2020]

Yup. We really only need 30-40Gb for basic DCOS, though the users may disagree. I would try 80GB initially

[jackfrancis]

Standard_D2s_v3 looks to only expose 16GB, so changing the minimum from ~100GB to ~80GB will still exclude Standard_D2s_v3.

[yakman2020]

So, I don't see how that could be correct. I'm deploying on D2s_v3 and they have 32GB main memory and a 128 gb system disk. Something is wrong with that data, albeit I'm specifying the size of the OS disk.

[yakman2020]

not correct. OK. My D3s instance is 40GB system disk. That is fine. Presumably I can specify larger in the deployment.

[jackfrancis]

lgtm