Update to 1.5100
    
    - New upstream release 1.5100
      - Moved code to github
      - Added xz support (CPAN RT#68286)
      - Added lzip support (http://sourceforge.net/p/grepmail/patches/8/)
      - Added POD test
      - Fixed hang in pure Perl implementation for a malformed mbox file scenario
      - Fixed $OLDSTDERR used only once warning (CPAN RT#58053)
      - Fixed enabling of warnings (CPAN RT#79898)
      - Fixed a division by zero error for malformed mbox files that start with a
        newline (CPAN RT#69469)
      - Fix bug in M::M::Perl documentation
      - Add more cache file validation
    - Classify buildreqs by usage
    - Add patch to fix build error (CPAN RT#103025)
    - Use %license where possible
    - Drop %defattr, redundant since rpm 4.4