Travis badge in readme file

Author: Norbert Kozlowski

README.md

@@ -1,12 +1,16 @@
 # LCS environment
 The repository contains environments used in LCS literature that are compliant with OpenAI Gym interface.
 
+[![Build Status](https://travis-ci.org/ParrotPrediction/openai-envs.svg?branch=master)](https://travis-ci.org/ParrotPrediction/openai-envs)
+
+
 ## Currently implemented environments
 
 - Maze (different variants)
 - Binary Multiplexer
 - Real Multiplexer
 - Hand Eye
+- Checkerboard
 
 For usage examples look at [examples/](examples) directory.
 
@@ -17,4 +21,4 @@ For usage examples look at [examples/](examples) directory.
 
     pip install -r requirements.txt
 
-    make test
+    make test