added npm & build badges to readme

Author: jakesgordon

README.md

@@ -1,5 +1,8 @@
 # Javascript State Machine
 
+[![NPM version](https://img.shields.io/npm/v/javascript-state-machine.svg?style=flat)](https://www.npmjs.org/package/javascript-state-machine)
+[![Build Status](https://travis-ci.org/jakesgordon/javascript-state-machine.svg?branch=master)](https://travis-ci.org/jakesgordon/javascript-state-machine)
+
 A library for finite state machines.
 
 ![matter state machine](examples/matter.png)