Test of the HTML/SGML comment syntax, as given in the W3 HTML Spec:
   [1]Comments

   See especially, the footnote: [2](10)

   Co-vary the LYK_MINIMAL and LYK_HISTORICAL command key toggles (use the
   'k'eymap command to see their key bindings) to establish Valid, Minimal
   or Historical comment parsing, and toggle trace mode on (Ctrl-T), to
   see how comment parsing is affected.

   Case 01 through Case 14 should appear as short separate paragraphs with
   the case numbers aligned vertically. Some noise characters may appear
   to the right as a byproduct of code present for error recovery, but
   there should be no noise before each case number.

   Case | 01 | Trivial

   Case | 02 | Hyphens and Spaces

   Case | 03 | Extra LT --> --> -->

   Case | 04 | Balanced

   Case > still in comment --> | 05 | Extra GT

   Case | 06 | Stuff Inside

   Case | 07 | Extra Open --> -->

   Case | 08 | New line

   Case | 09 | Degenerate

   Case | 10 | Empty

   Case | 11 | Perverse --> --> -->

   Case | 12 | Multiple Comments --> --> -->

   Case | 13 | Zero Comments

   Case | 14 | Last

   <Tests completed!>

References

   1. http://www.w3.org/hypertext/WWW/MarkUp/html-spec/html-spec_3.html#SEC15
   2. http://www.w3.org/hypertext/WWW/MarkUp/html-spec/html-spec_foot.html#FOOT10