as 'url' and 'title' and that are used in
'episode_navbar.html'.
- When episode order is specified manualy, the 'lesson_episodes'
+ When episode order is specified manually, the 'lesson_episodes'
variable contains a list of episode names ("slugs", to be precise;
"slug" is the episode name without '.md'). Therefore, when we
iterate over 'lesson_episodes' (in syllabus.html and navbar.html) ,