Annotations

Added separate annotations for cbg vs smbg. Merged with latest master. Ready for review.
Restoring something similar to the old logic here (i.e., the `if (opts.d.annotations[0].code !== 'stats-insufficient-data')`) will also fix the y-anchors of the tooltips on the two-week view, because all the stats-related ones used to have their `opts.y` adjusted a few lines below when the `container.type` is `weekly`.