Also create target directories in docker_build_copy and update readme

 shell script do not assume they are called from a directory in the project home, but called from the project home while the scripts themeselves might be somewhere else

Other scripts already assumes that so it should not have much impact, it allows more possibility for the location of the scripts

 run shell linters

Rely on the metaproject clone URL instead of its directory name. Works fine
with the bitbucket.org ➔ orus.io move.

TG-70

In the loop:
- Rename the "module" variable to "module_path".
- Set up a new "module" variable that contains nothing but the actual module
  name.

With a single underscore, the "link target" system is used, resulting in
conflicts when the same version name is shared by 2 repos.

docker_build: copy modules (defined in setup.cfg in superproject to a new directory for docker to do)