Replaces non-ASCII accented and other characters with HTML entities.
The non-ASCII characters replaced are, generally:
  aeiou with acute, circumflex, grave, ring above, tilde, or diaeresis;
  slashed O and o;
  ae and AE ligatures;
  c and C with cedilla;
  ess;
  n and N with tilde;
  single and double quotes.
Certain non-ASCII characters are not handled:
  ETH, THORN, Y acute, division, eth, thorn, times, y acute.
Input is taken from files named on the command line or from STDIN.
Options:
  -h, -help      Show this help.
  -e, -entities  List the HTML entities in the input.
  -n, -non-ASCII List the non-ASCII characters (by their entity names)
                   in the input [default].
  -r, -replace   Print the input with non-ASCII characters replaced by
                   entities.
  -w, -where     Show where each non-ASCII character or entity appeared.