Update README.rst

Author: kennknowles

README.rst

@@ -6,7 +6,7 @@ https://github.com/kennknowles/python-jsonpath-rw
 |Build Status| |Test coverage| |PyPi version| |PyPi downloads|
 
 This library provides a robust and significantly extended implementation
-of JSONPath for Python. It is tested with Python 2.6, 2.7, 3.2, and 3.3.
+of JSONPath for Python. It is tested with Python 2.6, 2.7, 3.2, 3.3, and PyPy.
 
 This library differs from other JSONPath implementations in that it is a
 full *language* implementation, meaning the JSONPath expressions are