#37 Support fileno() function in the socket protocol

[Herve Schnitzler]

If the socket protocol had a fileno() function, it would allow the Serial object to be used with select().
This prevents pySerial socket protocol to be used for example with the pexpect module.

Can the socket protocol (serial.urlhandlers.protocol_socket.py) use the socket.fileno()?
I tried it and it seems to work properly under linux. I'm not sure if there is an easy way to make win32 working.

# worked under linux if I added this to serial.urlhandlers.protocol_socket.py
def fileno(self):
    return self._socket.fileno()

[Chris Liechti]

makes sense, committed