python 2 deprecation

[chfw]

in 2020, new project are not likely to be running under python 2

[jayvdb]

pypi-mobans is used for maintaining old projects also. :p

But I dont have any py2 projects.

This should wait until pyexcel, moban, etc all drop py2. Any other projects which use moban that we need to check?

[chfw]

You are right! Spot on!