Merge bitcoin#13184: RPC Docs: gettxout*: clarify bestblock and unspe…

…nt counts

f30e9be RPC Docs: gettxout*: clarify bestblock and unspent counts (David A. Harding)

Pull request description:

  Expounds on two things I've seen confuse inexperienced users:

  - transactions/outputs in `gettxoutsetinfo`: a user thought this was the total number of transactions or outputs ever seen on the chain, whereas it's only the number in the UTXO.

  - bestblock in `gettxout`: a user thought this was the block that included the output, not realizing it was the tip of the current best block chain.  I also copied this text to `gettxoutsetinfo` for congruency.  I skimmed other uses of "bestblock" in the RPC docs and they seemed clear to me.

Tree-SHA512: c2161c497bef5fe15ee9f1e2a4413fa099b5baa36205ba1ba4b3822885b3ccd1badb9c118a0334f47ba6fa7fff5818ac359cfac6a1108c6847a876b1a251bb7c

src/rpc/blockchain.cpp

@@ -958,9 +958,9 @@ static UniValue gettxoutsetinfo(const JSONRPCRequest& request)
             "\nResult:\n"
             "{\n"
             "  \"height\":n,     (numeric) The current block height (index)\n"
-            "  \"bestblock\": \"hex\",   (string) the best block hash hex\n"
-            "  \"transactions\": n,      (numeric) The number of transactions\n"
-            "  \"txouts\": n,            (numeric) The number of output transactions\n"
+            "  \"bestblock\": \"hex\",   (string) The hash of the block at the tip of the chain\n"
+            "  \"transactions\": n,      (numeric) The number of transactions with unspent outputs\n"
+            "  \"txouts\": n,            (numeric) The number of unspent transaction outputs\n"
             "  \"bogosize\": n,          (numeric) A meaningless metric for UTXO set size\n"
             "  \"hash_serialized_2\": \"hash\", (string) The serialized hash\n"
             "  \"disk_size\": n,         (numeric) The estimated size of the chainstate on disk\n"
@@ -1003,7 +1003,7 @@ UniValue gettxout(const JSONRPCRequest& request)
             "     Note that an unspent output that is spent in the mempool won't appear.\n"
             "\nResult:\n"
             "{\n"
-            "  \"bestblock\" : \"hash\",    (string) the block hash\n"
+            "  \"bestblock\":  \"hash\",    (string) The hash of the block at the tip of the chain\n"
             "  \"confirmations\" : n,       (numeric) The number of confirmations\n"
             "  \"value\" : x.xxx,           (numeric) The transaction value in " + CURRENCY_UNIT + "\n"
             "  \"scriptPubKey\" : {         (json object)\n"