CIF language tutorial: split lesson on annotations into multiple lessons

Currently, we have one lesson to introduce what annotations are in general, as well as explain all the built-in annotations. It is getting longer and longer. Currently it discussed 4 built-in annotations. We'll likely soon be adding more annotations, such as in #679 and #1296.

I think it is time to split the lesson in multiple lessons, keeping the general introduction of annotations where it is, but moving each of the specific annotations to their own lessons. Some of them are longer than others, but it is OK to have shorter lessons, I think (there is precedent for it). I don't see grouping of multiple built-in annotations into a single lesson as an option, for the current annotations.