ms-vscode.csharp to ms-dotnettools.csharp

Author: devlead

CONTRIBUTING.md

@@ -22,7 +22,7 @@ This project depends on .NET Core 2.0. Before working on the project, check that
 This project supports [Visual Studio 2017](https://visualstudio.com) and [Visual Studio for Mac](https://www.visualstudio.com/vs/visual-studio-mac/). Any version, including the free Community Edition, should be sufficient so long as you install Visual Studio support for .NET Core development.
 
 This project also supports using
-[Visual Studio Code](https://code.visualstudio.com). Install the [C# extension](https://marketplace.visualstudio.com/items?itemName=ms-vscode.csharp) and install the [.NET Core CLI](https://get.dot.net/core) to get started.
+[Visual Studio Code](https://code.visualstudio.com). Install the [C# extension](https://marketplace.visualstudio.com/items?itemName=ms-dotnettools.csharp) and install the [.NET Core CLI](https://get.dot.net/core) to get started.
 
 ### Command line scripts