* Group notification emails by board
Notification bundle emails now group items by board instead of
showing the board name redundantly for each card. Each board
section has a linked header and an <hr> separator.
* Adjust board title styles and remove rem units
* Sort board groups alphabetically
Sort notification email board sections alphabetically by name
(case-insensitive).
Also, rewrite mailer tests to use Nokogiri::HTML5 for precise DOM
assertions instead of regex matching.
---------
Co-authored-by: Andy Smith <andy@37signals.com>
Mike Dalessio
8c5b47d774