In order to target some framework packages in Visual Studio 2017 RC, you should ensure that you have the latest Windows Insider Preview release installed. This will require that you participate in the Windows Insider Program, which is Microsoft's platform for distributing pre-release versions of Windows 10 and the accompanying .NET Framework SDK's.
when following this tutorial. after completing step one, you should close the terminal (or maybe open a new terminal window before attempting to run the commands instructed in step three as you will likely get the error "dotnet command not found".
the gist i've deployed the xos.mvc.framework nuget package which offers base model classes, controllers, and commonly used attribute filters for mvc projects as well as some nifty jquery and css plugins/helpers aimed to speed up asp.net mvc application development. the framework can be found on nuget.org. the source code is also available on github.