Update README.md - Add Docs badge (#2752)

Adds Docs badge.

Author: danieldegroot2

README.md

@@ -15,6 +15,8 @@ MapRoulette is an OpenStreetMap U.S. [Charter Project](https://openstreetmap.us/
 
 ## Using MapRoulette
 
+[![Docs](https://img.shields.io/badge/Docs-Learn-darkcyan?style=flat-square&logo=data:image/png;base64,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)](https://learn.maproulette.org/)
+
 If you're looking to improve OSM using MapRoulette, you can get started at [maproulette.org](https://maproulette.org) right away. You can log in to MapRoulette with your existing OSM account. If you don't have an OSM account, you probably want to learn the basics of mapping with OSM first. The best way to do this is to [create your very own OSM account](https://www.openstreetmap.org/user/new), move the map to your home town, and click "Edit" on the OSM web site. The OSM web editor has a built in walk-though that teaches you the basics. Once you have mastered basic OSM editing, you can use your new OSM account to log on to MapRoulette and start finding some easy tasks!
 
 All documentation for MapRoulette is at [learn.maproulette.org](https://learn.maproulette.org/). This site has resources for both mappers and those interested in developing their own MapRoulette Challenges.