Add detection of more OP_RETURN based data protocols

[kristapsk]

Currently Omni protocol is detected, but nothing more. Need to investigate others too, as without detecting them, there are some false positives in CoinJoin detection because of that. Blockcypher supports detection of blockchainid, openassets, factom, colu and coinspark in addition to omni (https://www.blockcypher.com/dev/bitcoin/#tx).

Example Colu tx that's incorrectly flagged as possible cj currently - https://live.blockcypher.com/btc/tx/f05d65e93da260aeb59de776396454c9d20e9da86817a70b573a0fc8189ed73f/.

[kristapsk]

Colu tx that's incorrectly flagged as possible cj currently

After a9b7986, any OP_RETURN transactions are assumed not being coinjoins (as no known implementation produces OP_RETURN outputs currently AFAIK), so coinjoin detection false positive is no more an issue. Still, would be good to have OP_RETURN protocol detectioin for checktransacion.sh, so keeping this open.