Add asyncio trove classifier (#69)

Author: alefteris

setup.py

@@ -42,7 +42,9 @@ def read(f):
           'Programming Language :: Python :: 3',
           'Programming Language :: Python :: 3.3',
           'Programming Language :: Python :: 3.4',
-          'Topic :: Internet :: WWW/HTTP'],
+          'Topic :: Internet :: WWW/HTTP',
+          'Framework :: AsyncIO',
+      ],
       author='Andrew Svetlov',
       author_email='[email protected]',
       url='https://github.com/aio-libs/aiohttp_security/',