This feature adds ARM Templates support for azure launch configs.
Current implementation is using resource by resource provisioning (and deprovisioning) which becomes very slow with the rising number of workers to check.

ARM Templates allow single async operation (start + check status calls) to trigger deployment and let Azure resource manager figure out full provisioning.
And if template is crafted correctly (deleteOption: Delete for resources), it would also allow to deprovision instance quickly, removing all dependent resources automatically.

There is also a requirement for template to include proper outputs for its resources. (to be documented and validated)

This allows azure to accept arm template deployments in launch configs.

TODO:

• schema change
• documentation with instructions how to craft templates
• add template spec validator for required outputs to be present
• add ARMDeploymentsClient.js since azure doesn't provide js sdk for it (yet), only REST API
• change provisioner and scanner to be aware of armDeployments in launch configs

Implements: #7979