[WIP] Microsoft.PowerShell.DSC module

[Gijsreyn]

PR Summary

As mentioned in the previous PR at: #498, the name might be too ambitious, but I thought to give it a shot.

The goal of the module is to help PowerShell users write DSC V3 configuration documents and resources in a PowerShell-ish way. This helps users adopt DSC V3 concepts by relating known commands on the shell to DSCV1/V2 concepts.

Features to include:

• Argument completers for PSDSC DSC resources. It should be able to output PowerShell objects that in the end are sent through the pipeline to dsc.exe as JSON.
• Provide easy-to-use examples from the get-go.
• Able to execute both .json, .yaml, or .ps1 files.
• Leverage functionality from adapters e.g. PowerShell/WindowsPowerShell
• ...

From this perspective in PS module format, it should be able to be checked for multiple PowerShell versions thanks to @gaelcolas and other contributors to the Sampler project. It can also be published easily in PowerShellGallery.