[FR] Documentation for absolute beginners

It would be great to include a couple of sentences about how to even get started with using perspective in the first place, assuming zero knowledge of the package. I had to go to the systemcrafters website to finally figure out that you have to do a C-x C-x s and give a new name to a perspective for something meaningful to happen... My preference is that these sentences would appear somewhere on the very top of the README :-)