ChefExtension support in the azure sdk toolkit

Contribution to the Azure SDK Toolkit from Chef - To support ChefExtension cmdlets.
Note - ClogenyTechnologies has a contract with Chef. We have signed the Microsoft CLA. This new PR has been created to accomodate the "rebase" after this repo had been restructured.
Original PR - https://github.com/Azure/azure-sdk-tools/pull/2576
@muktaa Based on the conditions you described above for the Client.rb file, why not just two parameter sets ?
1) ClientRb mandatory
 2) ClientServerUrl & OrganizationName mandatory

Wouldn't these give you the information you need.