SDK changes for repo management.

[dhoehna]

To better support the Azure extension, and other extensions where information is needed to grab a list of relevant repositories, the SDK needs to be updated to allow DevHome to pass information user provided information back to an extension.

An example is the Azure extension. The Azure extension needs three (Two for cloud servers) pieces of information.

1. The server
2. Organization
3. Project

This is to track

1. Implementing the SDK changes
2. Testing the SDK changes
3. Making a sample
4. Adding documentation