Fixes #1830 adds link to development guide (#2783)

README.md

@@ -48,6 +48,10 @@ If you would like, you can [support the development of this project on Patreon][
 - **Deployable via Docker**
   You don't need to mess with dependencies and configuration if you want to try Mastodon, if you have Docker and Docker Compose the deployment is extremely easy
   
+## Development
+
+Please follow the [development guide](https://github.com/tootsuite/documentation/blob/master/Running-Mastodon/Development-guide.md) from the documentation repository.
+
 ## Deployment
 
 There are guides in the documentation repository for [deploying on various platforms](https://github.com/tootsuite/documentation#running-mastodon).