Point at the latest 3.x docs in the URL on the PyPI

Author: ambv

setup.py

@@ -47,7 +47,7 @@
       long_description=long_description,
       author='Guido van Rossum, Jukka Lehtosalo, Łukasz Langa',
       author_email='[email protected]',
-      url='https://docs.python.org/3.5/library/typing.html',
+      url='https://docs.python.org/3/library/typing.html',
       license='PSF',
       keywords='typing function annotations type hints hinting checking '
                'checker typehints typehinting typechecking backport',