mention python version 3.3

Author: chfw

setup.py

@@ -33,6 +33,7 @@
     'Intended Audience :: Developers',
     'Programming Language :: Python :: 2.6',
     'Programming Language :: Python :: 2.7',
+    'Programming Language :: Python :: 3.3',
     'Programming Language :: Python :: 3.4',
     'Programming Language :: Python :: 3.5',
     'Programming Language :: Python :: 3.6',