Renamed node_api and node_storage by blog_api and blog_storage in related CMS_BLOG_* classes. Mainly to avoid confusion with NODE_ classes.

Merged CMS_BLOG_CONFIG with CMS_BLOG_API.
In CMS_BLOG_API, prefer argument of type CMS_USER, rather than using directly user id.
Added a CMS_EDITOR_CONTENT_FORMAT for now, to be the format editable by the WYSIWYG editor.
Added CMS_MODULE.is_initialized: BOOLEAN to equip router, and module_api with expected preconditions.

Fixed typo, especially in log output.
Corrected a few routine names such as add_authors that should not be a function according to its name.
Converted various function returning html content, to procedure appending html content to an output string to minimize temporary string object creation.
Cosmetic: added spaces to make code easier to read, and indentation.

examples/demo/modules/blog/handler/cms_blog_handler.e

@@ -10,7 +10,14 @@ deferred class
 inherit
 	CMS_MODULE_HANDLER [CMS_BLOG_API]
 		rename
-			module_api as node_api
+			module_api as blog_api
+		end
+
+feature -- Access
+
+	entries_per_page: NATURAL_32
+		do
+			Result := blog_api.entries_per_page
 		end
 
 end