Migration guide for mdakits

[IAlibay]

When we do a major change to the behaviour of the cookiecutter, e.g. changing from versioneer to versioningit, would it be useful to leave some kind of short set of migration information for folks that already have an mdakit generated?

Not a full length tutorial, but a couple of sentences with some references?

[RMeli]

This would be very helpful! Even more helpful would be some sort of tool to automate most of it, but I think that's way more complicated and probably out of scope.