feat(azure-iothub): add AAD authentication

[zolvarga]

Checklist

• [ ] I have read the [contribution guidelines] (https://github.com/Azure/azure-iot-sdk-node/blob/master/.github/CONTRIBUTING.md).
• [ ] I added or modified the existing tests to cover the change (we do not allow our test coverage to go down).
• If this is a modification that impacts the behavior of a public API
  • [ ] I edited the corresponding document in the devdoc folder and added or modified requirements.

Reference/Link to the issue solved with this PR (if any)

Description of the problem

Description of the solution

[zolvarga]

/azp run

[azure-pipelines[bot]]

Azure Pipelines successfully started running 2 pipeline(s).

[anthonyvercolano]

/azp run node-canary

[azure-pipelines[bot]]

Pull request contains merge conflicts.