Results archiving

Added results archiving.
Result files are archived if the number of .json files exceeds n (specified in config). For each n files, a new archive is created (encoding specified in config).
Archive files are deleted after being sent to the server.
The result file is created exactly once after all of the experiments have finished running and the program will exit after this is done. There is just no point in storing this as it's not used anywhere else in the code.