Update templates with info on where the interactive parts should go

[HeidiSeibold]

We need to have information on the templates on how to include interactivity.

I think we should have three types of interactive parts (let me know if you disagree):

• Multiple choice questions Example:

• Runnable code Example:

• Code questions

  • empty code blocks with solutions Example:
  • prepared code blocks with changes to be made plus solutions

[HeidiSeibold]

My suggestions

• All code blocks should in exercise = TRUE so that people need to run it to see the output
• At the end of each section (FIND, ANALYSE, ...) there should be at least one exercise with either a code question (exercise = TRUE plus solution) or a multiple choice question