update: Added installation steps to README.md
update: Added installation steps to README.md

* Added a few rudimentary installation steps to README.md so that any
  random passer-by won't get lost right away.

Signed-off-by: mr.Shu <8e7be411ad89ade93d144531f3925d0bb4011004@shu.io>

mrshu/brutal-plugins