Add missing classifier (#121)

Co-authored-by: Anton Benkevich <[email protected]>

Author: anton-b

setup.py

@@ -19,6 +19,7 @@
         'Intended Audience :: Developers',
         'License :: OSI Approved :: MIT License',
         'Natural Language :: English',
+        'Programming Language :: Python :: 3.5',
         'Programming Language :: Python :: 3.6',
         'Programming Language :: Python :: 3.7',
         'Programming Language :: Python :: 3.8'