Allow a variant of the build that is built without docker.

To allow a build without docker, reusable parts are moved from
make.sh to common.sh and a new make-without.docker.sh is doing the very same
steps that the Makefile did.

Targets:

- Ensure the the same build parameters are used in both variants

- Make clear that this build wont be supported by the project if anything
  breaks.

- Provide a better readable script than the previous Makefile.


This variant is says clearly that build errors will not be supported.