[Review] Request from 'aduffeck' @ 'SUSE/pennyworth/review_140804_improve_ssh_key_upload'

Please review the following changes:
  * cf437fc Allow for specifying the SSH key that should be uploaded
  * 51fe997 Make ssh-key-upload script more robust
  * 48bf5ff Merge pull request #3 from SUSE/review_140731_add_missing_exception_class
  * ada3481 Add missing exception class