change PerlHandler -> PerlResponseHandler in docs

According to
http://perl.apache.org/docs/2.0/user/handlers/http.html#HTTP_Request_Cycle_Phases
"the PerlHandler directive has been renamed to PerlResponseHandler to
better match the corresponding Apache phase name (response)."
Reflect changes and update list of contributors.
Merge branch 'Xaerxess-pr/fix-doc-apache2-deployment'