Fixes: https://pagure.io/koji/issue/913
I wonder if we should make relative the default. Also , this function might belong in koji.util.
rebased onto 3a3a314f20e530e331c68e3b9afcc16a84f93f08
updated
Commit 0e043e1e fixes this pull-request
Pull-Request has been merged by mikem
Fixes: https://pagure.io/koji/issue/913