Use caret shorthand to open links in new tab

[HonkingGoose]

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

Changes

• Use the caret ^ shorthand to open links in a new tab ^docs
• Drop a double newline at the end of a file

Context

Fixes #1604.