Structure ci/pipeline script. (#5768)
Structure ci/pipeline script. (#5768)

Summary:
This is just a tiny restructuring of the pipeline script so that targets
are easier to find.
meln1k/marathon,mesosphere/marathon,meln1k/marathon,mesosphere/marathon,meln1k/marathon,mesosphere/marathon,janisz/marathon,gsantovena/marathon,janisz/marathon,mesosphere/marathon,meln1k/marathon,janisz/marathon,meln1k/marathon,mesosphere/marathon,guenter/marathon,guenter/marathon,guenter/marathon,guenter/marathon,gsantovena/marathon,gsantovena/marathon,gsantovena/marathon,janisz/marathon,janisz/marathon,gsantovena/marathon,guenter/marathon