HOT for MSSQL Server with unit tests

It deploys an MSSQL Server instance.
The MSSQL ISO file is copied from an SMB share.

The unit tests for the powershell module(user data scripts) are written
using Pester 3.0

Change-Id: If2b024d7717e2846bb199e950c314ce9c9d778e7
Partially-Implements: blueprint windows-instances