Guided tour

[erinharrington-12]

This PR is a guided visual tour for using the Classroom functionality. Features include:

• Pop-up box to give user some info about what the highlighted section is.
• Next, Back and Skip buttons to guide the user through the tour.
• Interactive steps that guide the user how to create classrooms, add students to classrooms, etc.
• Brief overview of Dashboard
• Users can retake tour at any time using the "Retake Tour" button added to MainMenu.tsx
• Potential features to add would be to pick up in the Classroom's Teacher View to guide user through functionality after adding a student to the created classroom.