** The "ckout" CHECKIN is intended for development - to provide a mechanism
** for looking at what a file will look like using the /doc webpage after
** it gets checked in.
**
** The file extension is used to decide how to render the file.
**
** If FILE ends in "/" then names "FILE/index.html", "FILE/index.wiki",
** and "FILE/index.md" are  in that order.  If none of those are found,
** and "FILE/index.md" are tried in that order.  If none of those are found,
** then FILE is completely replaced by "404.md" and tried.  If that is
** not found, then a default 404 screen is generated.
*/
void doc_page(void){
  const char *zName;                /* Argument to the /doc page */
  const char *zOrigName = "?";      /* Original document name */
  const char *zMime;                /* Document MIME type */