Now for something completely different: default branch rename to ... default

[sthagen]

I propose to create a branch default, make it the default branch, and after safely merging from master remove the master branch for good. We have no slave branches in the repo, so, no master needed, I guess. Also, We rarely have the luck, to find really canonical names in software and standards development 😉 Other name candidates to me sound weird. For example:

latest as well as main are bad choices for the default branch in most cases. The docker harbor choice gives many users the impression of latest and greatest, but sometimes it is only latest and producers can label whatever they like latest in the docker docks. The term main is also often misleading, as we tend to not offer subsidiaries.

The 8 forks are mostly from TC members and also their owners are easy to contact, to avoid any bad mood in our neighborhood when executing this change.