chore(coveralls): add coverage badge

- add coveralls badge to readme

[#162265205]

README.md

@@ -1,7 +1,7 @@
 
 Authors Haven - A Social platform for the creative at heart.
 =======
-[![Reviewed by Hound](https://img.shields.io/badge/Reviewed_by-Hound-8E64B0.svg)](https://houndci.com) [![CircleCI](https://circleci.com/gh/andela/valinor-ah-frontend/tree/master.svg?style=svg)](https://circleci.com/gh/andela/valinor-ah-frontend/tree/master)
+[![Reviewed by Hound](https://img.shields.io/badge/Reviewed_by-Hound-8E64B0.svg)](https://houndci.com) [![CircleCI](https://circleci.com/gh/andela/valinor-ah-frontend/tree/develop.svg?style=svg)](https://circleci.com/gh/andela/valinor-ah-frontend/tree/develop) [![Coverage Status](https://coveralls.io/repos/github/andela/valinor-ah-frontend/badge.svg?branch=develop)](https://coveralls.io/github/andela/valinor-ah-frontend?branch=develop)
 ## Vision
 
 Our vision is to create a community of like minded authors to foster inspiration and innovation by leveraging the modern web.