Coveralls implementation and badges

.gitignore

@@ -1,4 +1,6 @@
 /node_modules/
 node_modules/
 node_modules
-/.vscode
+/.vscode
+coverage
+.nyc_output

.travis.yml

@@ -1,3 +1,4 @@
 language: node_js
 node_js:
-  - "stable"
+  - "stable"
+after_script: npm run coverage

README.md

@@ -1,3 +1,7 @@
+[![npm](https://img.shields.io/npm/v/chrome-webstore-stats)](https://www.npmjs.com/package/chrome-webstore-stats)
+[![Build Status](https://travis-ci.org/navi1995/Chrome-Webstore-Stats.svg?branch=master)](https://travis-ci.org/navi1995/Chrome-Webstore-Stats)
+[![David](https://img.shields.io/david/navi1995/chrome-webstore-stats)](https://david-dm.org/navi1995/chrome-webstore-stats)
+[![Coverage Status](https://coveralls.io/repos/github/navi1995/Chrome-Webstore-Stats/badge.svg?branch=master)](https://coveralls.io/github/navi1995/Chrome-Webstore-Stats?branch=master)
 # Chrome Webstore Stats 
 This is a simple node module used to provide details of any given chrome webstore's extension ID (32 alpha string from end of webstore link) or ARRAY of extension IDs.