it popped up to my mind that our current versioning scheme is a bit
painful whenever we need to insert an unexpected release: e.g.
when we've put out 1.3.1, it "stole" a version number that was
"reserved", which can result in some confusion, e.g. when looking up
planning information in past email.
Perhaps we should call all our expected releases a.b.c, and "bonus"
intermediary releases a.b.c.d? In the case at hand, instead of 1.3,
1.3.1 and 1.3.2, this would have given 1.3.0, 1.3.0.1, and 1.3.1.