Fix staff model IDs
Fix staff model IDs

First staff ID is now the parent container element (section), since a
<sb> shouldn't kick off the musical content.

DDMAL/Neon.js,avorio/Neon.js,avorio/Neon.js,DDMAL/Neon.js,DDMAL/Neon.js,avorio/Neon.js,avorio/Neon.js,DDMAL/Neon.js