george/prediction_tracker: Manage and score predictions on arbitrary topics.

George C. Privon 23e8a801ca re-format(indent) code		5 lat temu
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create_database.rkt	976166a797 improve require formatting	6 lat temu
scoring_rules.rkt	7d3b4d3c4a type annotations, more appropriate computation of log score	6 lat temu
update_predictions.rkt	23e8a801ca re-format(indent) code	5 lat temu