Extracted page support from cms_node_module, and add a proper CMS_PAGE_MODULE.

- now, the CMS_PAGE_MODULE has to be declared in the related CMS_SETUP via CMS_EXECUTION.
   (See demo for example)

Improved the export facilities.
  Implemented blog and page export.
Added import facilities.
  Implemented blog and page import.

Improved node revision web interface (allow to edit a past revision, in order to restore it as latest revisionm i.e current).
Removed specific tag from blog module, and reuse the taxonomy module for that purpose.

Added WIKITEXT module that provide a WIKITEXT_FILTER, so now we can have wikitext content.
   - for now, no support for wiki links such as [[Foobar]].

modules/node/export/cms_export_node_utilities.e

@@ -11,11 +11,15 @@ class
 inherit
 	CMS_EXPORT_JSON_UTILITIES
 
+	CMS_API_ACCESS
+
 feature -- Access
 
-	node_to_json (n: CMS_NODE): JSON_OBJECT
+	node_to_json (n: CMS_NODE; a_node_api: CMS_NODE_API): JSON_OBJECT
 		local
-			jo,j_author: JSON_OBJECT
+			jo: JSON_OBJECT
+			ja: JSON_ARRAY
+			j, jterm: JSON_OBJECT
 		do
 			create Result.make_empty
 			Result.put_string (n.content_type, "type")
@@ -27,10 +31,7 @@ feature -- Access
 			put_date_into_json (n.publication_date, "publication_date", Result)
 			Result.put_integer (n.status, "status")
 			if attached n.author as u then
-				create j_author.make
-				j_author.put_integer (u.id, "uid")
-				j_author.put_string (u.name, "name")
-				Result.put (j_author, "author")
+				Result.put (user_to_json (u), "author")
 			end
 			create jo.make_empty
 			if attached n.format as l_format then
@@ -44,12 +45,41 @@ feature -- Access
 			end
 			Result.put (jo, "data")
 			if attached n.link as lnk then
-				create jo.make_empty
-				jo.put_string (lnk.title, "title")
-				jo.put_string (lnk.location, "location")
-				jo.put_integer (lnk.weight, "weight")
-				Result.put (jo, "link")
+				Result.put (link_to_json (lnk), "link")
+			end
+
+			if attached {CMS_TAXONOMY_API} a_node_api.cms_api.module_api ({CMS_TAXONOMY_MODULE}) as l_taxonomy_api then
+				if
+					attached l_taxonomy_api.terms_of_content (n, Void) as l_tags and then
+					not l_tags.is_empty
+				then
+					create ja.make (l_tags.count)
+					across
+						l_tags as ic
+					loop
+						create jterm.make_with_capacity (2)
+						jterm.put_integer (ic.item.id, "id")
+						jterm.put_string (ic.item.text, "text")
+						ja.extend (jterm)
+					end
+					Result.put (ja, "tags")
+				end
 			end
 		end
 
+	user_to_json (u: CMS_USER): JSON_OBJECT
+		do
+			create Result.make
+			Result.put_integer (u.id, "uid")
+			Result.put_string (u.name, "name")
+		end
+
+	link_to_json (lnk: CMS_LOCAL_LINK): JSON_OBJECT
+		do
+			create Result.make_empty
+			Result.put_string (lnk.title, "title")
+			Result.put_string (lnk.location, "location")
+			Result.put_integer (lnk.weight, "weight")
+		end
+
 end