Upgraded to python 3.6

[casimiro]

No description provided.

[tiangolo]

Thanks!

But I think we should preserve a "3.5" tag, for backward compatibility, as many users would already be relying on a tag "3.5".

Could you please, instead of replacing the "3.5" with the "3.6", add a new "3.6" version?

[tiangolo]

Thanks for your effort @casimiro , this was included in #6 .