Update README description of tested versions

Author: bd808

README.md

@@ -64,7 +64,8 @@ Local documentation can be built using [Sphinx][]:
 Python Version Compatibility
 ----------------------------
 
-[Travis CI][ci-home] automatically runs tests against python 2.6, 2.7, 3.2, 3.3 and pypy.
+[Travis CI][ci-home] automatically runs tests against python 2.7, 3.4, 3.5,
+pypy, and pypy3,
 
 Installation
 ------------