Update CPython versions

I don't know about the PyPy versions as it is not in the change or history.

README.rst

@@ -1,7 +1,7 @@
 Waitress is meant to be a production-quality pure-Python WSGI server with very
 acceptable performance.  It has no dependencies except ones which live in the
 Python standard library.  It runs on CPython on Unix and Windows under Python
-2.6+ and Python 3.2+.  It is also known to run on PyPy 1.6.0+ on UNIX.  It
+2.7+ and Python 3.3+.  It is also known to run on PyPy 1.6.0+ on UNIX.  It
 supports HTTP/1.0 and HTTP/1.1.
 
 For more information, see the "docs" directory of the Waitress package or