Syllabus Accordion

[tcp]

Currently, it is hard to reference the syllabus both in terms of scan-ability and interaction.

• [x] Truncate the lesson description (After 477 characters, truncate)
• [ ] Give locked concepts a disable state (@tcp will take this task)
• [x] Allow user to click any unlocked concept to skip directly to that concept page
• [x] Underline concept name on hover