Nyzo 637: transaction send command binary sender data

Nyzo version 637 (commit on GitHub) adds support for binary sender data in the TransactionSendCommand.

This version affects the client.

We initially intended for this version to include the nickname script. However, in sending the transaction to establish the nickname script account, we realized that support for binary sender data was still needed in the TransactionSendCommand. This version corrects that deficiency.

In TransactionSendCommand.validate(), the ClientTransactionUtil.isNormalizedSenderDataString() method is now used to detect and pass through normalized sender-data strings. Text sender data is processed as it was previously, and the truncation message is now passed to the argument result.

In TransactionSendCommand.run(), the ClientArgumentUtil.getSenderData() method is now used to process the sender-data argument.