Added blocks.p2pool.observer/proofs that explains more about Miner Proof Verification plus information for any pools that want to opt-in/disclose proof methods

[CCS Proposals] Kaŝmaristo Delvakto opened merge request #615: Memoro Vault Bounty Challenge (36 XMR Security Demonstration) repo.getmonero.org/monero-project/ccs-proposals/-/merge_requests/615