Extracted createPipeHandlerCallback method
Extracted createPipeHandlerCallback method

- from the pipe() method

Maks3w/zend-stratigility,matwright/zend-stratigility,liuggio/zend-stratigility,codeliner/zend-stratigility,xtreamwayz/zend-stratigility,Diego-Brocanelli/zend-stratigility,jguittard/zend-stratigility