Move all open issues from closed milestone to next mini release

[beberlei]

Feature Request

Q	A
New Feature	yes
RFC	yes/no
BC Break	yes/no

Summary

Instead of failing with an assertion that there are still open issues on the milestone, the release tool could move all issues to the next milestone.

[Ocramius]

IMO to be avoided: this failsafe is precisely in place to prevent releasing when a release is not ready.

Releasing is up to the tool, but release management is really up to a maintainer.

[beberlei]

Then the tool at least should reopen the milestones

[Ocramius]

Hmm, IMO letting it crash seems reasonable - it's a failsafe to prevent releasing by accident, after all 🤔