[Review] Request from 'aduffeck' @ 'SUSE/machinery/review_141114_fix_comparing_unmanaged_files'

Please review the following changes:
  * 159547f Fix empty lines in unmanaged files list when files were not extracted
  * 930787e Do not choke on lacking file lists when rendering unmanaged files scopes
  * 9a81ab3 Only consider common attributes when comparing UnmanagedFileLists
Prefer `detect` over `find`.