Update to 1.863
    
    - New upstream release 1.863
      - Use MCE::Channel for MCE::Hobo->yield not to incur unnecessary delays due
        to busy shared-manager process
      - Re-factored recent changes regarding IPC safety in MCE::Shared::Server;
        this update defers signal handling for HUP, INT, PIPE, QUIT, TERM, and
        custom handlers during IPC without incurring a performance penalty (see
        POD section labled "DEFER SIGNAL" in MCE::Signal 1.863)
      - Reverted $hobo->exit back to sending the SIGQUIT signal in MCE::Hobo now
        that MCE::Shared::Server defers signal during IPC
      - Improved reliability for spawning MCE::Hobo inside threads including nested
        parallelization, made possible using a global lock $MCE::_GMUTEX in MCE
        1.863
      - Updated signal handling in mce-examples/framebuffer on GitHub
      - Bumped MCE dependency to 1.863