Adds an exercise block to the end of a chapter

Adds an exercise block to the end of a chapter

add_exercise(chapter_file = "chapter1.md", exercise_id = "01_01")

Arguments

chapter_file

- name of the chapter, such as "chapter1.md" without the path
exercise_id

- id of the exercise, such as "01_03"

Value

- opened files including the chapter file, with the new exercise/codeblock appended and the exercises opened