store package

Package store keeps Gnogolf's data (every record, best, board, standing, round in play and hole) apart from its rules, so a new version of the rules takes the data on instead of starting empty. It knows nothing of golf: a few ordered collections of string keys to string values, written only by the one realm it names as its writer (the rules: golf/v2 at the launch), read by anyone. A new writer takes over three days after its code is on chain and says so (the owner proposes it, it calls Ready), on its own; the owner can stop every write at once (Pause), start the same rules again at once (Resume), and renounce the role for good.