What if a textfile ends without a newline?

As this is not mentioned in the Mastering Go, 3rd edition book, I have included separate version of byWord.go, byLine.go and byCharacter.go named byWord_noNewLine.go, byLine_noNewLine.go and byCharacter_noNewLine.go, respectively that show how to handle plain text files that do not end with a newline character.

Enjoy!