Make message printable by changing plain carriage return characters "\r" to carriage return and newline characters "\r\n".
Printable string, with "\r" characters changed to "\r\n"
HL7 messages use the carriage return character "\r" to separate the segments. This makes it difficult to print them out in console windows because the cursor overwrites each previous segment instead of moving on to a newline for each segment. This method is intended to be a simple utility method to make it easier to convert HL7 messages into a printable format. This function also allows the output string to be truncated.