Improved taxonomy by supporting tags, multiple terms allowed, and required kind of vocabulary for specific content type.

Updated node web form, to support taxonomy editing if allowed (specific support for CMS_VOCABULARY.is_tags: BOOLEAN).
Added notion of required or optional module dependencies.

src/service/cms_module.e

@@ -29,8 +29,8 @@ feature -- Access
 	version: STRING
 			-- Version of the module?
 
-	dependencies: detachable LIST [TYPE [CMS_MODULE]]
-			-- Optional dependencies.
+	dependencies: detachable LIST [TUPLE [module_type: TYPE [CMS_MODULE]; is_required: BOOLEAN]]
+			-- Optional declaration for dependencies.
 
 	permissions: LIST [READABLE_STRING_8]
 			-- List of permission ids, used by this module, and declared.
@@ -55,16 +55,22 @@ feature {CMS_API} -- Module Initialization
 		end
 
 	add_dependency (a_type: TYPE [CMS_MODULE])
-			-- Add dependency using type of module `a_type'.
-		local
-			deps: like dependencies
+			-- Add required dependency using type of module `a_type'.
 		do
-			deps := dependencies
-			if deps = Void then
-				create {ARRAYED_LIST [TYPE [CMS_MODULE]]} deps.make (1)
-				dependencies := deps
+			put_dependency (a_type, True)
+		end
+
+	put_dependency (a_type: TYPE [CMS_MODULE]; is_required: BOOLEAN)
+			-- Add required or optional dependency using type of module `a_type', based on `is_required' value.
+		local
+			lst: like dependencies
+		do
+			lst := dependencies
+			if lst = Void then
+				create {ARRAYED_LIST [TUPLE [module_type: TYPE [CMS_MODULE]; is_required: BOOLEAN]]} lst.make (1)
+				dependencies := lst
 			end
-			deps.force (a_type)
+			lst.force ([a_type, is_required])
 		end
 
 feature -- Status