Supporting Inner Source with Forks

Introduces the ability to fork Git repositories hosted in Visual Studio Team Services (VSTS). This enables a fork-based pull request workflow, which is popular for open-source projects and also supports Inner Source practices within companies. Developers can create a duplicate copy of a repository, experiment safely in their fork, and then open a pull request back to the original repository without needing write access. The post details the UI for creating forks and opening pull requests across forks.