Making PoCo::Server::TCP subclassable

[Arthur Bergman]

As I am redesigning PoCo::Server::HTTP  wanted to make PoCo::Server::HTTP a subclass 
of of Poco::S::TCP.
Currently this is impossible so I end up having two sessions, one which handles the 
new socket and one which handles the request, this is inefficent at best.

So I propose that PC::S::TCP has a constructor argument which is called inside it's 
_start.

POE::Component::Server::TCP->new( Port => $self->{Port}, Acceptor => sub {}, 
Constructor => {});

Arthur