Publish new version to pypy

[marcosfelt]

First off, great package!

There are some recent features such as Interface.from_class() that justify publishing a new version to pypy. It looks like the pypy distribution hasn't been updated since December 2017.

[ssanderson]

👍 I'll try to push out a new release some time this week.

[marcosfelt]

Sounds good!

[ssanderson]

Just released 1.5.0. https://github.com/ssanderson/interface/releases/tag/1.5.0.