New upstream release.

• osbuild: test passing of rich repos from configuration (lsedlar)
• osbuild: support specifying package_sets for repos (thozza)
• osbuild: don't use util.get_repo_urls() (thozza)
• osbuild: update schema and config documentation (thozza)
• Speed up tests by 30 seconds (lsedlar)
• Stop sending compose paths to CTS (lsedlar)
• Report errors from CTS (lsedlar)
• createiso: Create Joliet tree with xorriso (lsedlar)
• init: Filter comps for modular variants with tags (lsedlar)
• Retry failed cts requests (hlin)
• Ignore existing kerberos ticket for CTS auth (lsedlar)
• osbuild: support specifying upload_options (thozza)
• osbuild: accept only a single image type in the configuration (thozza)
• Add Jenkinsfile for CI (hlin)
• profiler: Flush stdout before printing (lsedlar)