New RPC Argument
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- `sendrawtransaction` has a new, optional argument, `maxburnamount` with a default value of `0`. Any transaction containing an unspendable output with a value greater than `maxburnamount` will not be submitted. At present, the outputs deemed unspendable are those with scripts that begin with an `OP_RETURN` code (known as 'datacarriers'), scripts that exceed the maximum script size, and scripts that contain invalid opcodes.