Timestamp Communication and Structure

[maluethi]

As decided yesterday in the meeting we syncronise laser events with TPC events based on timing information: The system time of the laser server is garatueed to be in sysnc within 1ms to the GPS time of the TPC data. The laser data timestap is then used to sync the laser data to the TPC data in the assembler.
At the moment the timestamp is generated in the c-code when an new UDP packet arrived at the computer, not more. An implementation of sending / recieving and writing is needed, first we need to define the data structure.