Removed Transaction::TCP, created Modbus::Message
Created Modbus::TCP to gather common code between server and client
Modbus::Server::TCP reworked to new api, untested
Client and example server work. Changes need to be ported to Server::TCP
Device::Modbus::Server::TCP updated with changes to naked_server.pl example program
Moved transaction routines out from Client::TCP to Modbus::Client
Added Modbus::RTU and Modbus::Client::RTU, untested