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Technical Overview
  internal package Foswiki::Engine::Legacy  
This engine supports legacy bin scripts that don't use
$Foswiki::cfg{SwitchBoard} yet.
It redefines 
Foswiki::Request::new and 
Foswiki::Response::new, so request and
response objects are singletons, making it possible to the engine finalization
phase invoked from the END block happens.