Update viewing-history.asc

[shallow-beach]

• 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

• make explicit note about shortcut

Context

Draws attention to a shortcut not previously demonstrated. Easily missed (by me).

[michaelblyons]

I think instead of adding a note there, it might be better to modify the text in the table on line 223.

-| `--pretty`        | Show commits in an alternate format. Option values include `oneline`, `short`, `full`, `fuller`, and `format` (where you specify your own format).
+| `--pretty`        | Show commits in an alternate format. Option values include `oneline`, `short`, `full`, `fuller`, or specify your own format.