Update to 1.817
    
    - New upstream release 1.817
      - Fixed broken SIG{'PIPE'} handling: e.g. script.pl | head
      - Improved reliability when running MCE::Shared with threads
      - Added parallel Net::Pcap and Ping demonstrations on Github:
        https://github.com/marioroy/mce-examples/tree/master/network
      - Default to ':raw' for BINMODE in MCE::Shared::Handle
      - Optimized 'dequeue' method in MCE::Shared::Queue
      - Refactored MCE::Hobo to spawn children on the Windows platform
      - Bumped MCE dependency to 1.821
    - Update Sereal dependency patch