Ensure that the <H> message is sent on the serial USB (to JMRI) whenever the turnout is closed or thrown, even if the request didn't originate on the serial USB.
Turnout class split into a base class for common code and specific subclasses for Servo, DCC, VPIN and LCN turnouts.
Interface further narrowed to reduce direct access to member variables.
Turnout creation command handling has been moved into the DCCEXParser class.
Turnout function and parameter names changed to make the Throw and Close functionality explicit.
Turnout commands <T id C> (close) and <T id T> (throw) added.
On activation, Turnout code was saving entire EEPROM twice, even if EEPROM save was switched off with the <e> command. It's now been changed so that only the tStatus byte is updated, and only if the turnout has previously been saved into EEPROM.
In prep for Wifi siolution, all output functions changed to expect Print class instead of Stream... Can still pass Serial1 etc because Stream extends Print, but this allows for an output-only class extending Print to collect a response buffer for Wifi sending with AT commands.
