Compatibility with gcc-avr 4.7.x

Note: this is a quick & dirty fix that turns on the deprecated
functions in the compiler. A more thorough fix is necessary in the
near future.
Accept of tcp packets refactored to a separate method

I refactored the 'accept' part of the packet loop method into a separate
method, to able to call it several times, with different ports.

This is a very quick fix, and might creates conflicts under heavy load.
Limitations:
 - accept only a single packet
 - every incoming packet should be serviced before accepting a new packet.

To accept an additional port, one should do the following:

  word pos;
  word plen = ether.packetReceive();

  // check if valid tcp data is received
  if (plen) {
    // handle the default port, that has been set in 'hisport' variable
    if ((pos = ether.packetLoop(plen))) {
      serviceHttpRequest(bfill, pos);
    }
    // if the packet is for our second port, then handle it
    else if ((pos = ether.accept(10050, plen))) {
      serviceZabbixRequest(bfill, pos);
    }
  }
Merge pull request #73 from mrbig/f/multi_port

F/multi port and Arduino compatibility fix