Log operations

[harnen]

Currently, we write all the messages to a csv file but we don't know how they're a part of an operation. To fix that, we should log operations as well. This should be designed for the Find Operation and we can later extend it other types as well.

To complete this task we need:

1. Keep a time when an operations started
2. Keep IDs of all the messages that were sent within this operations
3. Record the time of operation termination
4. Report the operation to Kademlia Observer. We already have a system built for writing everything to files, so it's enough to create a map that contains feature -> value mapping (a similar thing is done for messages).

The final CSV file should look something like that:

id,src,type,messages, start, stop
3640,1294132996371968615893927407296059812556716358774,OP_FIND,3640|2306|3638,55,87