Support for Azure Devops Server 2019

[nairsajith]

This works nicely for Azure Devops Services, would have been great if it could be extended for the onprem version as well.

[valtynikov]

@nairsajith thanks for the feedback!

Yes, I agree that it'd be great to have an implementation that works with Azure DevOps Server but I'm afraid Azure DevOps CLI only works with Azure DevOps Services at this time so the solution would require much more coding and testing.

I'm definitely willing to accept a PR if someone would like to implement it!