Update to 0.73
    
    - New upstream release 0.73
      - Support for gpg under these alternate names: gpg gpg2 gnupg gnupg2
      - Don't check gpg version if gpg does not exist
      - Constrain the user-specified digest name to /^\w+\d+$/
      - Only allow loading Digest::* from absolute paths in @INC (CVE-2013-2145)
    - This release by AUDREYT -> update source URL
    - Include Andreas Koenig's GPG key in the SRPM and import it in %prep so
      that we don't need to get it from a keyserver in %check
    - Make building non-interactive
    - Specify all dependencies
    - Don't need to remove empty directories from the buildroot
    - Drop %defattr, redundant since rpm 4.4
    - Use %{_fixperms} macro rather than our own chmod incantation