scribble: use 'attributes' properties when rendering table cells

svn: r18488

collects/scribble/html-render.ss

@@ -1122,6 +1122,13 @@
                                     (string? (style-name column-style)))
                                `([class ,(style-name column-style)])
                                null)
+                         ,@(if (and column-style
+                                    (pair? (style-properties column-style)))
+                               (style->attribs (make-style
+                                                #f
+                                                (filter attributes? 
+                                                        (style-properties column-style))))
+                               null)
                          ,@(if (and (pair? (cdr ds))
                                     (eq? 'cont (cadr ds)))
                                `([colspan

collects/scribblings/scribble/core.scrbl

@@ -853,13 +853,16 @@ The following symbols are recognized as cell-@tech{style properties}:
 
  @item{@scheme['vcenter] --- Center the cell content vertically.}
 
-]}
+]
 
+In addition, for HTML output, @scheme[attributes] structures as
+@tech{style properties} can add arbitrary attributes to a cell's
+@tt{<td>} tag.}
 
 @defstruct[table-columns ([styles (listof style?)])]{
 
 Like @scheme[table-cells], but the @scheme[styles] list is duplicated
-for each row in the table. This @tech{style property} is only when a
+for each row in the table. This @tech{style property} is used only when a
 @scheme[table-cells] is not present in a style's list of properties.}
 
 @defproc[(block? [v any/c]) boolean?]{