Modified "ShowTable.pm":

  Added "showmode" argument to ShowTableValue so it could handle HTML
  embedded text correctly.  ShowTableValue now uses a string substitution
  "%s" for any values with embedded HTML tokens, even if defined as an
  integer or real.

  Changed how URLs work: now %K and %V are substituted into the URL
  corresponding to the given field name key.  No other insertions are
  done, so the URL is completely specified by the user otherwise.

  Added tableAttrs argument to ShowHTMLTable allowing other stuff to be
  inserted within the TABLE token (ie: <TABLE $table_attrs>).

  Changed the regexp in &PlainText to avoid the multiple null string
  matches.

  Changed htmltext to substitute blanks if the optional second argument
  is non-null (which is used when creating URLs).

  Allow column indexes, as well as column names, to be mapped to URLs.

  Added %I (column index) key to the url substitutions.

  Removed Sys::OutPut usage.  Added "put" and "out" subs directly.

  Fixed small documentation problems.

Modified "showtable":

  Added -urls option to support URL mappings for fields.

  Added -attributes option to support table_attributes argument.

Added Changes file.

Added t/html-urls.t test file.
