Revert "* Attempting to overhaul the .note class system. Everything is now subdued: .notevoid is removed, .note will do a similar job; while .note will be replaced by .notewarn (orange hue), and the original .notewarn disappears (too visible for my current taste). The .notenice class remains, but gets a more pastel tone. (Boards.template.php, MessageIndex.template.php, index.template.php, index.css, sections.css)"

This reverts commit 02dd0528d5d9020eb6feefcdda0ebf90759b824d.

@ Note: leaving sections.css untouched, this one was okay. The rest was... Not particularly popular, and I did say I'd probably revert the commit.