Add docs badge

README.md

@@ -1,5 +1,6 @@
 
 [![Build Status](https://travis-ci.org/tripal/tripal_blast.svg?branch=7.x-1.x)](https://travis-ci.org/tripal/tripal_blast)
+[![Documentation Status](https://readthedocs.org/projects/tripal-blast-ui/badge/?version=latest)](https://tripal-blast-ui.readthedocs.io/en/latest/?badge=latest)
 
 INTRODUCTION
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