Added wsf_html documentation in the doc/workbook.

Also improved the structure of `wsf_html` library.
Added a few widgets.

library/server/wsf_html/widget/wsf_widget_div.e

@@ -0,0 +1,90 @@
+note
+	description : "Objects that ..."
+	author      : "$Author$"
+	date        : "$Date$"
+	revision    : "$Revision$"
+
+class
+	WSF_WIDGET_DIV
+
+inherit
+	WSF_WIDGET
+
+	WSF_WIDGET_COMPOSITE
+
+	WSF_WITH_CSS_ID
+
+	WSF_WITH_CSS_CLASS
+
+	WSF_WITH_CSS_STYLE
+
+	WSF_WITH_HTML_ATTRIBUTE
+
+create
+	make,
+	make_with_item,
+	make_with_items,
+	make_with_text,
+	make_with_text_and_css_id,
+	make_with_item_and_css_id
+
+feature {NONE} -- Initialization
+
+	make
+			-- Initialize `Current'.
+		do
+			initialize_with_count (0)
+		end
+
+	make_with_text (s: READABLE_STRING_8)
+		do
+			make_with_item (create {WSF_WIDGET_TEXT}.make_with_text (s))
+		end
+
+	make_with_item (i: WSF_WIDGET)
+		do
+			initialize_with_count (1)
+			extend (i)
+		end
+
+	make_with_items (it: ITERABLE [WSF_WIDGET])
+		do
+			initialize_with_count (2)
+			across
+				it as c
+			loop
+				extend (c.item)
+			end
+		end
+
+	make_with_item_and_css_id (i: WSF_WIDGET; a_css_id: READABLE_STRING_8)
+		do
+			make_with_item (i)
+			set_css_id (a_css_id)
+		end
+
+	make_with_text_and_css_id (s: READABLE_STRING_8; a_css_id: READABLE_STRING_8)
+		do
+			make_with_text (s)
+			set_css_id (a_css_id)
+		end
+
+feature -- Conversion
+
+	append_to_html (a_theme: WSF_THEME; a_html: STRING_8)
+		do
+			a_html.append ("<div")
+			append_css_class_to (a_html, Void)
+			append_css_id_to (a_html)
+			append_css_style_to (a_html)
+			append_html_attributes_to (a_html)
+			a_html.append (">")
+			across
+				items as c
+			loop
+				c.item.append_to_html (a_theme, a_html)
+			end
+			a_html.append ("</div>%N")
+		end
+
+end