Introduce MPT support (XLS-33d): (#5143)

Amendment:
- MPTokensV1

New Transactions:
- MPTokenIssuanceCreate
- MPTokenIssuanceDestroy
- MPTokenIssuanceSet
- MPTokenAuthorize

Modified Transactions:
- Payment
- Clawback

New Objects:
- MPTokenIssuance
- MPToken

API updates:
- ledger_entry
- account_objects
- ledger_data

Other:
- Add += and -= operators to ValueProxy

Read full spec: https://github.com/XRPLF/XRPL-Standards/tree/master/XLS-0033d-multi-purpose-tokens

---------
Co-authored-by: Shawn Xie <shawnxie920@gmail.com>
Co-authored-by: Howard Hinnant <howard.hinnant@gmail.com>
Co-authored-by: Ed Hennis <ed@ripple.com>
Co-authored-by: John Freeman <jfreeman08@gmail.com>

src/test/jtx/impl/trust.cpp

@@ -64,13 +64,19 @@ trust(
 }
 
 Json::Value
-claw(Account const& account, STAmount const& amount)
+claw(
+    Account const& account,
+    STAmount const& amount,
+    std::optional<Account> const& mptHolder)
 {
     Json::Value jv;
     jv[jss::Account] = account.human();
     jv[jss::Amount] = amount.getJson(JsonOptions::none);
     jv[jss::TransactionType] = jss::Clawback;
 
+    if (mptHolder)
+        jv[sfHolder.jsonName] = mptHolder->human();
+
     return jv;
 }