2.9 version of the Open Build Service Server

This is the maintained, released version 2.9 of OBS.

Any development for further 2.9 releases (2.9.*) happens in the OBS:Server:2.9:Staging project.

An overview of our setup can be found in our development documentation at https://github.com/openSUSE/open-build-service/wiki/Overview-of-OBS%3AServer%3A%24VERSION