• Refactored all display specific code out of TAP::Harness.
  
• Relaxed strict parsing of skip plan for pre v13 TAP.
  
• Elapsed hi-res time is now displayed in integer milliseconds
  instead of fractional seconds.
  
• prove stops running if any command-line switches are invalid.
  
• prove -v would try to print an undef.
  
• Added support for multiplexed and forked parallel tests. Use
  prove -j 9 to run tests in parallel and prove -j 9 --fork to
  fork. These features are experimental and currently
  unavailable on Windows.
  
• Rationalized the management of the environment that we give to
  test scripts (PERL5LIB, PERL5OPT, switches).
  
• Fixed handling of STDIN (we no longer close it) for test
  scripts.
  
• Performance enhancements. Parser is now 30% - 40% faster.