Merge pull request openai#78 from jkterry1/patch-1

Link to maintained fork in readme

Author: pzhokhov

README.md

@@ -1,5 +1,7 @@
 **Status:** Archive (code is provided as-is, no updates expected)
 
+A maintained version of these environments, with numerous fixes, is included with PettingZoo (https://github.com/PettingZoo-Team/PettingZoo , https://www.pettingzoo.ml/mpe)
+
 # Multi-Agent Particle Environment
 
 A simple multi-agent particle world with a continuous observation and discrete action space, along with some basic simulated physics.