documentation is here: http://michele.sciabarra.com/2016/06/17/scala/ScalaGoodies/
In short:
git remote add ScalaGoodies https://github.com/sciabarra/ScalaGoodies
git fetch --all
If you want an advanced sbt:
git merge ScalaGoodies/esbt
If you want Scala completions and reformatting with Atom:
git merge ScalaGoodies/completion
If you want a notebook, both external (Jupyter) and internal in Atom (Hydrogen):
git merge worksheet
Then complete with
bin/install.sh
That's all.