Add tip: use verbose CLI flags for shared scripts

[HonkingGoose]

• I provide my work under the project license.
• I grant such license of my work as is required for the purposes of future print editions to Ben Straub and Scott Chacon.

Changes

• Add tip: use verbose CLI flags for shared scripts

Context

Implements one of the wanted changes for issue #720:

Put a note somewhere which says "if you're writing a script that others will need to read, prefer the long versions of command-line flags; six months from now you'll thank us."

[HonkingGoose]

Hi @ben, the hooks section of the book seems a logical place to put this tip? Or do you have a better place for it? 😉

[ben]

Perfect.