Log Message:
py-hg-evolve: update to 10.3.1.

This is a bugfix release that addresses various issues and adds
compatibility with the upcoming Mercurial 5.8. Check the changelog for
details. The most notable changes are: cache reuse on different systems
(such as using 64-bit and 32-bit Python to push/pull the same repo)
should now be safe, and hg next now handles unstable changesets with
topics more correctly.