[Review] Request from 'aduffeck' @ 'SUSE/machinery/review_140815_do_not_extract_broken_files'

Please review the following changes:
  * 8c9941f Also exclude files with broken filenames from the tarball
  * 717b3c7 Allow for excluding specific files when creating an archive
  * 1742f7a Merge pull request #93 from SUSE/review_140815_log_warnings
  * 99681f0 Also write warnings about broken filenames to the log file