Added feed aggregation module.

Redesigned the CMS_BLOCK system,
   - added condition attribute. It can be set via configuration file
     with
     [blocks]
      {blockid}.region={region_name}
      {blockid}.conditions[]=is_front
      {blockid}.conditions[]=path:location-path/foo/bar
   - For backward compatibility, the CMS will check only conditions for block name prefixed by "?".
Improved the configuration library to support list and table properties.
Updated theme for now, to include the feed examples.
Added "cache" classes, to ease caching of html output for instance. (TODO: improve by providing a cache manager).

modules/feed_aggregator/feed_aggregation.e

@@ -15,6 +15,8 @@ feature {NONE} -- Initialization
 		do
 			create name.make_from_string_general (a_name)
 			create {ARRAYED_LIST [READABLE_STRING_8]} locations.make (0)
+			expiration := 60*60
+			description_enabled := True
 		end
 
 feature -- Access
@@ -22,12 +24,23 @@ feature -- Access
 	name: IMMUTABLE_STRING_32
 			-- Associated name.
 
+	expiration: INTEGER
+			-- Suggested expiration time in seconds (default: 1 hour).
+			-- If negative then never expires.
+
 	description: detachable IMMUTABLE_STRING_32
 			-- Optional description.
 
 	locations: LIST [READABLE_STRING_8]
 			-- List of feed location aggregated into current.
 
+	included_categories: detachable LIST [READABLE_STRING_32]
+			-- Optional categories to filter.
+			-- If Void, include any.
+
+	description_enabled: BOOLEAN
+			-- Display description?
+
 feature -- Element change
 
 	set_description (a_desc: detachable READABLE_STRING_GENERAL)
@@ -39,4 +52,54 @@ feature -- Element change
 			end
 		end
 
+	set_expiration (nb_seconds: INTEGER)
+			-- Set `expiration' to `nb_seconds'.
+		do
+			expiration := nb_seconds
+		end
+
+	set_description_enabled (b: BOOLEAN)
+			-- Set `description_enabled' to `b'.
+		do
+			description_enabled := b
+		end
+
+	reset_categories
+		do
+			included_categories := Void
+		end
+
+	include_category (a_cat: READABLE_STRING_GENERAL)
+		local
+			lst: like included_categories
+			s32: STRING_32
+		do
+			lst := included_categories
+			if lst = Void then
+				create {ARRAYED_LIST [READABLE_STRING_32]} lst.make (1)
+				included_categories := lst
+				lst.compare_objects
+			end
+			s32 := a_cat.to_string_32
+			if not lst.has (s32) then
+				lst.force (s32)
+			end
+		end
+
+feature -- Status report
+
+	is_included (e: FEED_ITEM): BOOLEAN
+		do
+			Result := True
+			if attached e.categories as e_cats then
+				if attached included_categories as lst then
+					Result := across lst as ic some
+							across e_cats as e_ic some
+								e_ic.item.same_string (ic.item)
+							end
+						end
+				end
+			end
+		end
+
 end