Changed from CopyOnWriteArrayList to ArrayList and used synchronized blocks to make access to population thread-safe (note: now takes copy of the list instead of passing actual list around).

Changed each reward to only count intermediateReward given relating to the last go (as opposed to all gos upto this point).
Added weighting to similarity class, so squares nearer to Mario are considered more important than those further away.
LSMPOP file now contains 4000+ levelscenes.
Added sleep when waiting for save to finish before exiting program, so doesn't repeatedly print.