`getrawnotarytransaction` takes a transaction hash and attempts to find
the corresponding transaction in the notary requests mempool. It searches
through all the verified main and fallback transactions.
`getrawnotarypool` returns hashes of all the verified transactions,
including both main and fallback transactions.
Additionally add struct result.RawNotaryPool.
Close https://github.com/nspcc-dev/neo-go/issues/2951
Signed-off-by: Tatiana Nesterenko <tatiana@nspcc.io>
