Revisited the format, filter and content type integration.

Now, all formats used by CMS are instances of CMS_FORMAT, mainly to prepare the admin section in order to define format by config/database.
CMS_NODE_API provides all queries to access the content types, and formats, this way a module can easily alter the formats by adding a new filter.

TODO: see how to integrate permission checking, to control who can use a specific format (such as full HTML).

src/kernel/content/format/cms_format.e

@@ -0,0 +1,113 @@
+note
+	description: "Summary description for {CMS_FORMAT}."
+	author: ""
+	date: "$Date$"
+	revision: "$Revision$"
+
+class
+	CMS_FORMAT
+
+inherit
+	CONTENT_FORMAT
+
+create
+	make,
+	make_from_format
+
+feature {NONE} -- Initialization
+
+	make (a_name: READABLE_STRING_8; a_title: detachable READABLE_STRING_8)
+		do
+			default_create
+			name := a_name
+			set_title (a_title)
+			create filters.make (0)
+		end
+
+	make_from_format (a_format: CONTENT_FORMAT)
+		do
+			make (a_format.name, a_format.title)
+			import_filters_from_format (a_format)
+		end
+
+feature -- Access
+
+	name: STRING
+			-- <Precursor>
+
+	title: STRING
+			-- <Precursor>
+
+	filters: ARRAYED_LIST [CONTENT_FILTER]
+			-- <Precursor>
+
+	filter (a_name: READABLE_STRING_GENERAL): detachable CONTENT_FILTER
+			-- Filter named `a_name' if any.
+		do
+			across
+				filters as ic
+			until
+				Result /= Void
+			loop
+				if a_name.is_case_insensitive_equal (ic.item.name) then
+					Result := ic.item
+				end
+			end
+		end
+
+feature -- Element change
+
+	set_title (a_title: detachable READABLE_STRING_8)
+			-- Set `title' according to `a_title' or `name' if `a_title' is blank.
+		do
+			if a_title = Void or else a_title.is_whitespace then
+				create title.make_from_string (name)
+			else
+				title := a_title
+			end
+		end
+
+	import_filters_from_format (f: CONTENT_FORMAT)
+		do
+			across
+				f.filters as ic
+			loop
+				add_filter (ic.item)
+			end
+		end
+
+	add_filter (f: CONTENT_FILTER)
+		require
+			has_no_such_filter: filter (f.name) = Void
+		do
+			filters.extend (f)
+		ensure
+			has_filter: filter (f.name) = f
+		end
+
+	remove_filter_by_name (a_name: READABLE_STRING_GENERAL)
+			-- Remove filter named `a_name' if any.
+		local
+			lst: like filters
+		do
+			from
+				lst := filters
+				lst.start
+			until
+				lst.after
+			loop
+				if a_name.is_case_insensitive_equal (lst.item.name) then
+					lst.remove
+				else
+					lst.forth
+				end
+			end
+		ensure
+			filter_removed: filter (a_name) = Void
+		end
+
+
+note
+	copyright: "2011-2015, Jocelyn Fiat, Javier Velilla, Eiffel Software and others"
+	license: "Eiffel Forum License v2 (see http://www.eiffel.com/licensing/forum.txt)"
+end