Adding missing installation step to readme. Fixes #13

Author: raphaelokon

readme.md

@@ -3,7 +3,7 @@
 > Command-line interface (CLI) for the patternlab-node core.
 
 ## Installation
-Coming soon …
+`npm install pattern-lab/patternlab-node-cli`
 
 ## Getting Started
 1. In order to use PatternLab you need to initialize a PatternLab project with `patternlab init`. The CLI will ask you some setup question and scaffold your project based on it.