Update classifiers
Explicitly list supported Python versions.
@@ -31,7 +31,13 @@ Development Status :: 5 - Production/Stable
License :: OSI Approved :: Apache Software License
Operating System :: OS Independent
Programming Language :: Python :: 2
+Programming Language :: Python :: 2.6
+Programming Language :: Python :: 2.7
Programming Language :: Python :: 3
+Programming Language :: Python :: 3.3
+Programming Language :: Python :: 3.4
+Programming Language :: Python :: 3.5
+Programming Language :: Python :: 3.6
Programming Language :: Python :: Implementation :: CPython
Programming Language :: Python :: Implementation :: Jython
Programming Language :: Python :: Implementation :: IronPython
