WIP:Add docker build support based on openSUSE images

The scripts used by this mr have been taken from the dbus project and adapted to create kmymoney and run tests on linux distributions. Since these scripts are independent of the .gitlab-ci.yml syntax, the same scripts can be used to build kmymoney and run tests on a local docker instance or even on a local distribution for the purpose of verification and debugging not possible on remote CI systems like KDE gitlab. Extensions for other distributions can be easily added.

Using that script on KDE CI is not wanted yet, so the associated gitlab-ci.yml entry is disabled by default.