fix(README): fix scoped package name

With the move to monorepo, we were able to shorten `patternlab-node` to `core`

Author: bmuenzenmeyer

README.md

@@ -8,7 +8,11 @@ This monorepo contains the core of Pattern Lab / Node and all related engines, U
 
 If you'd like to see what a front-end project built with Pattern Lab looks like, check out this [online demo of Pattern Lab output](http://demo.patternlab.io/).
 
-[![Build Status](https://travis-ci.org/pattern-lab/patternlab-node.svg?branch=master)](https://travis-ci.org/pattern-lab/patternlab-node) ![current release](https://img.shields.io/npm/v/@pattern-lab/patternlab-node.svg) ![license](https://img.shields.io/github/license/pattern-lab/patternlab-node.svg) [![Coverage Status](https://coveralls.io/repos/github/pattern-lab/patternlab-node/badge.svg?branch=master)](https://coveralls.io/github/pattern-lab/patternlab-node?branch=master) [![code style: prettier](https://img.shields.io/badge/code_style-prettier-ff69b4.svg)](https://github.com/prettier/prettier)
+[![Build Status](https://travis-ci.org/pattern-lab/patternlab-node.svg?branch=master)](https://travis-ci.org/pattern-lab/patternlab-node)
+![current release](https://img.shields.io/npm/v/@pattern-lab/core.svg)
+![license](https://img.shields.io/github/license/pattern-lab/patternlab-node.svg)
+[![Coverage Status](https://coveralls.io/repos/github/pattern-lab/patternlab-node/badge.svg?branch=master)](https://coveralls.io/github/pattern-lab/patternlab-node?branch=master)
+[![code style: prettier](https://img.shields.io/badge/code_style-prettier-ff69b4.svg)](https://github.com/prettier/prettier)
 [![node (scoped)](https://img.shields.io/node/v/@pattern-lab/patternlab-node.svg)]()
 [![Join the chat at Gitter](https://badges.gitter.im/pattern-lab/node.svg)](https://gitter.im/pattern-lab/node)