Update README.md

I made a few suggestions :x

At first I thought, :astonished: - wow BEM is way easy to get setup.  I couldn't believe my eyes.

Then, I thought I'd help the README out a little bit...  So, I started editing.  Then I was half-way through a writing what I thought should be here... when I realized that I was **wrong**.  So, I kept writing and writing and writing... And by the time I got to the end of writing, I feel like I finally got it, and maybe I helped the README after all ;P

I hope y'all also like my suggestions, but feel free to just :fire: this whole thing.