Test project for package tests using the OBS multibuild feature

See http://openbuildservice.org/help/manuals/obs-reference-guide/cha.obs.multibuild.html for reference.

https://build.opensuse.org/package/view_file/openSUSE:Factory/installation-images/installation-images.spec?expand=1 can serve as a good example as well as https://build.opensuse.org/package/view_file/openSUSE:Factory/python-pbr/python-pbr.spec?expand=1

http://s.qa.suse.de/2k18l1-okurz