fix(readme): Add coverage badge
diff --git a/README.md b/README.md
index 950f282..f4a08be 100644
--- a/README.md
+++ b/README.md
@@ -8,6 +8,7 @@
[](https://travis-ci.com/frappe/erpnext)
[](https://gitter.im/frappe/erpnext?utm_source=badge&utm_medium=badge&utm_campaign=pr-badge&utm_content=badge)
[](https://www.codetriage.com/frappe/erpnext)
+[](https://coveralls.io/github/frappe/erpnext?branch=develop)
[https://erpnext.com](https://erpnext.com)