Rarst/wporg-developer — pull request #23 by DrewAPicture (2014-09-22 23:31:28+00:00)
Title: Introduce callout box shortcodes for use in handbook and Code Ref articles.

Registers four new shortcodes, `[info]`, `[tip]`, `[alert]`, and `[warning]` and adds basic styling.

All four shortcodes use the basic syntax of `[open]Message[/close]`.

TODO: Add styling for the icons and any other tweaks the shortcodes' output markup.