Replay Functionality

[PGijsbers]

GAMA is currently not reproducible due to randomness in the timing of asynchronous tasks. While this may be alleviated by opting for different forms of parallelism, this is out of scope for now. It would be useful to have replay functionality in GAMA, meaning that given its log-file, GAMA can retrace its steps. From there, it should also be possible to pause GAMA arbitrarily and resume with different operators (mutation, selection, crossover, etc.).