[latexrefman] Added section on \stretch

[Hefferon, Jim S.]

Added small section with a couple of examples.  (I understand Lamport's book to say that the argument must be integral, but testing seems to me to show that it can be any number.)

Jim

...........................................................
The Tao gave birth to machine language. Machine language gave birth to
the assembler.  The assembler gave birth to the compiler. Now there are ten
thousand languages.  Each has its purpose, however humble. Each expresses
the Yin and Yang of software. Each has its place within the Tao.

But do not program in COBOL if you can avoid it.