Should upgraded project 'include' the MVC folder?

On my many-time-upgraded Sitefinity project, now at 5.1.3210.0, I now have the new MVC folder, but it is 'grayed out' in Visual Studio i.e. not included in my project file. Can I assume that it is ok to include the file into my project? Are there any other folders or files that should also be 'included' into my project?

Solved it! I was jumping ahead before I got down that far in the upgrade documentation. Sorry.

Cliff Notes answer: yes, you do need to include it and a few other files all well documented at the bottom of the page.

My thanks to the documentation team. Each version of the upgrade documentation is getting easier for me to follow.