Add reference in Getting Started for how to add flags for CMake

In this page:
https://github.com/conan-io/docs/blob/master/getting_started.rst

At the end of the page in Linux pullet point, it is mentioned "This can also be done more easily, by automatically using Conan, as we’ll show later."
Could we add here a link to the page that shows how to add CMake settings automatically using conan?