Add a "Table of Contents" to pages

[sc0ttj]

Create a function to generate a table of contents (TOC):

• to be used by screen readers (like the "Skip to content" link)
• put it below post/page h2 heading, above first para content body
• and optionally as an aside on large screens
• should output small menu of links to headers, something like:

1. h2 name
  2. h3 name
    a. h4 name
    b. h4 name
  3. h3 name
  4. h3 name
    a. h4 name
    b. h4 name

NOTE:

TOC should not be added to index pages (homepage, categories, authors, tags), the search page, or the contact page..