* replace bash function to list docker tags with https://github.com/genuinetools/reg/
* this depends on new release in https://github.com/genuinetools/reg/issues/186 to fully function
* update docker version
* fix version.sh to also show versions from repos defined in .env
* add script to list available tags and update values in .env
* define default values for all version vars
* add previously missing containers
* use command instead of hash in update env script
* use a custom select function instead shell builtin (since it does not handle default values)
* add setup-update-tag in test.exp
