Add linux dependencies to README.md (bevyengine#257)

* Add linux dependencies to README.md

* Update README.md

README.md

@@ -38,7 +38,10 @@ Bevy is still in the _very_ early stages of development. APIs can and will chang
 
 ## Getting Started
 
-We recommend checking out [The Bevy Book](https://bevyengine.org/learn/book/introduction) for a full tutorial. You can quickly try out the [examples](/examples) by cloning this repo and running the following command:
+We recommend checking out [The Bevy Book](https://bevyengine.org/learn/book/introduction) for a full tutorial.
+
+Follow the [Setup guide](https://bevyengine.org/learn/book/getting-started/setup/) to ensure your development environment is setup up correctly.
+Once setup, you can quickly try out the [examples](/examples) by cloning this repo and running the following command:
 
 ```sh
 # Runs the "breakout" example