Update parrot to version 4.1.0.

Upstream changes:

- Core
  + Shared libraries and installable binaries are now stripped if
    built with --optimize on Cygwin, which greatly reduces their
    size on disk
  + New experimental PCC-related ops added to core.
- Documentation
  + Revised 'docs/project/release_manager_guide.pod'
- Tests
  + Parrot now uses Travis CI http://travis-ci.org
  + Parrot Continuous Integration (CI) with Travis CI means
    every commit of Parrot is now compiled and tested on gcc,
    g++ and clang with various Configure.pl options.
  + CI Notifications are sent to parrot-dev, the #parrot
    IRC channel and Smolder
  + Cardinal and Rakudo spec tests also on Travis CI

(he)