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/protocol/Quality_test.cpp

@@ -29,7 +29,7 @@ public:
     // Create a raw, non-integral amount from mantissa and exponent
     STAmount static raw(std::uint64_t mantissa, int exponent)
     {
-        return STAmount({Currency(3), AccountID(3)}, mantissa, exponent);
+        return STAmount(Issue{Currency(3), AccountID(3)}, mantissa, exponent);
     }
 
     template <class Integer>