Skill tags / topics

[Skivling]

Most courses will spend the first several skills teaching basic grammar concepts and being an introduction to the language.

It would be nice to be able to add 'tags' or topics to skills, e.g. Travel, Work, School, Food. So later on in a course, skills could be designed to be focusing on certain topics that maybe not everyone wants to learn.

This could also be accompanied by a field which says 'complete [----] skill before beginning this one'. For example, complete Food skill before doing Ordering in a Restaurant.

There could be an extra file, topics.yaml, which defines the topics used in the course and includes a short description for each of them.