Automatically convert nested lists into collapsing menus

Book 1
Book 2
- Chapter 1
- Chapter 2
- Chapter 3
  - Collapsible List Example
  - Ex 2
  - DrillDown
    - Ex 21
    - Ex 22
    - DrillDown 2
      - Ex 31
      - Ex 32
- Chapter 4
Book 3

Alex Campbell has extended this version of the listCollapse.js script to allow it to work with autocollapsing.