def validate_syntax
      update_native
      validator = Bitcoin::Validation::Tx.new(@native, nil)
      valid = validator.validate :rules => [:syntax]
      {:valid => valid, :error => validator.error}
    end
def validate_syntax
      update_native
      validator = Bitcoin::Validation::Tx.new(@native, nil)
      valid = validator.validate :rules => [:syntax]
      {:valid => valid, :error => validator.error}
    end
Validate that the transaction is plausibly signable.