Fails when using many slots about p-net

[pyhys]

Changing the log level shows:

Parameter write call-back. AREP: 1 API: 0 Slot: 9 Subslot: 1 Index: 123 Sequence: 18 Length: 4
  Bytes: 00 00 00 00 
Parameter write call-back. AREP: 1 API: 0 Slot: 9 Subslot: 1 Index: 124 Sequence: 19 Length: 4
  Bytes: 00 00 00 00 
Parameter write call-back. AREP: 1 API: 0 Slot: 10 Subslot: 1 Index: 123 Sequence: 20 Length: 4
  Bytes: 00 00 00 00 
Parameter write call-back. AREP: 1 API: 0 Slot: 10 Subslot: 1 Index: 124 Sequence: 21 Length: 4
  Bytes: 00 00 00 00 
[DEBUG] BW(152): End of buffer reached
[DEBUG] BW(152): End of buffer reached
[DEBUG] BW(152): End of buffer reached
[DEBUG] BW(152): End of buffer reached
[DEBUG] BW(152): End of buffer reached
[DEBUG] BW(152): End of buffer reached
[DEBUG] BW(152): End of buffer reached
[DEBUG] BW(152): End of buffer reached
[DEBUG] BR(77): End of buffer reached
[ERROR] CMRPC(2498): Unknown packet_type 1

This is because the output buffer is full. It is implemented as 1500 bytes. Response message fragmentation is not yet implemented.

This is a duplicated of #34

[pyhys]

We have implemented a fix for this, see #62