Support Python 3.5's typing module (and backport)

[evanunderscore]

typing module: https://docs.python.org/3/library/typing.html backport: https://pypi.python.org/pypi/typing

Will need some extra logic to handle the new generic types properly. For example, Iterable[int] currently displays as typing.Iterable in the signature and as Iterable in the parameter description.

I may look into this if I get time.

[evanunderscore]

After some more searching, I've found https://github.com/agronholm/sphinx-autodoc-typehints, which appears to work correctly for my use cases. Given the discussion on #5, perhaps you could consider updating the readme to point people to that project as an alternative?