Update of IOUSniffer

- Only sniff for link where a DLT was found in the NETMAP
- Change the format of the DLT in the NETMAP: add “#” before the DLT (had to do this because of the IOU-WEB interface I use)
- Automatically add/delete sniffer attached to an IOU when added/deleted in the NETMAP file (through the check_file function)
- Change the format of the name’s file generated : iouID1_ifMajor1.ifMinor1-iouID2_ifMajor2.ifMinor2
- Don't register unix socket if socket id > 1000 (specific rule to work with IOUlive86 and only if you set IOUlive86 instance from 1000 to 1023.