Add asyncio trove classifier

Author: alefteris

setup.py

@@ -32,7 +32,9 @@ def read(name):
           'Programming Language :: Python :: 3.4',
           'Programming Language :: Python :: 3.5',
           'Programming Language :: Python :: 3.6',
-          'Topic :: Internet :: WWW/HTTP'],
+          'Topic :: Internet :: WWW/HTTP',
+          'Framework :: AsyncIO',
+      ],
       author='Andrew Svetlov',
       author_email='[email protected]',
       url='https://github.com/aio-libs/async_timeout/',