Add jss fields used by Clio nft_info: (#4320)

Add Clio-specific JSS constants to ensure a common vocabulary of
keywords in Clio and this project. By providing visibility of the full
API keyword namespace, it reduces the likelihood of developers
introducing minor variations on names used by Clio, or unknowingly
claiming a keyword that Clio has already claimed. This change moves this
project slightly away from having only the code necessary for running
the core server, but it is a step toward the goal of keeping this
server's and Clio's APIs similar. The added JSS constants are annotated
to indicate their relevance to Clio.

Clio can be found here: https://github.com/XRPLF/clio

Signed-off-by: ledhed2222 <ledhed2222@users.noreply.github.com>

src/ripple/protocol/jss.h

@@ -309,6 +309,7 @@ JSS(invalid_API_version);  // out: Many, when a request has an invalid
                            //      version
 JSS(io_latency_ms);        // out: NetworkOPs
 JSS(ip);                   // in: Connect, out: OverlayImpl
+JSS(is_burned);            // out: nft_info (clio)
 JSS(issuer);               // in: RipplePathFind, Subscribe,
                            //     Unsubscribe, BookOffers
                            // out: STPathSet, STAmount
@@ -413,6 +414,7 @@ JSS(nft_offer);                  // in: LedgerEntry
 JSS(nft_offer_index);            // out nft_buy_offers, nft_sell_offers
 JSS(nft_page);                   // in: LedgerEntry
 JSS(nft_serial);                 // out: account_nfts
+JSS(nft_taxon);                  // out: nft_info (clio)
 JSS(no_ripple);                  // out: AccountLines
 JSS(no_ripple_peer);             // out: AccountLines
 JSS(node);                       // out: LedgerEntry
@@ -585,6 +587,7 @@ JSS(transaction);             // in: Tx
 JSS(transaction_hash);        // out: RCLCxPeerPos, LedgerToJson
 JSS(transactions);            // out: LedgerToJson,
                               // in: AccountTx*, Unsubscribe
+JSS(transfer_rate);           // out: nft_info (clio)
 JSS(transitions);             // out: NetworkOPs
 JSS(treenode_cache_size);     // out: GetCounts
 JSS(treenode_track_size);     // out: GetCounts