Added a simple mimic.  Idea from Alkemade, F., and J. A. La Poutré.
“Heterogeneous, Boundedly Rational Agents in the Cournot Duopoly.” In
Heterogenous Agents, Interactions and Economic Performance, edited by
Prof Robin Cowan and Dr Nicolas Jonard, 3–17. Lecture Notes in Economics
and Mathematical Systems 521. Springer Berlin Heidelberg, 2003.
http://link.springer.com/chapter/10.1007/978-3-642-55651-7_1.