Remove unused artefact methods

Signed-off-by: Richard Mansfield <richardm@catalyst.net.nz>

htdocs/artefact/blog/lib.php

@@ -138,10 +138,6 @@ class ArtefactTypeBlog extends ArtefactType {
         }
     }
 
-    public function is_container() {
-        return true;
-    }
-
     /**
      * This function updates or inserts the artefact.  This involves putting
      * some data in the artefact table (handled by parent::commit()), and then

htdocs/artefact/lib.php

@@ -370,10 +370,6 @@ abstract class ArtefactType {
         }
     }
     
-    public function is_container() {
-        return false;
-    }
-
     /** 
      * This method updates the contents of the artefact table only.  If your
      * artefact has extra information in other tables, you need to override
@@ -635,16 +631,6 @@ abstract class ArtefactType {
     }
 
 
-    /**
-     * By default public feedback can be placed on all artefacts.
-     * Artefact types which don't want to allow public feedback should
-     * redefine this function.
-     */
-    public function public_feedback_allowed() {
-        return true;
-    }
-
-
     /**
      * By default users are notified of all feedback on artefacts
      * which they own.  Artefact types which want to allow this
@@ -687,13 +673,6 @@ abstract class ArtefactType {
      */
     public static abstract function is_singular();
 
-    /**
-     * Whether the 'note' field is for the artefact's private use
-     */
-    public static function is_note_private() {
-        return false;
-    }
-
     /**
      * Returns a list of key => value pairs where the key is either '_default'
      * or a langauge string, and value is a URL linking to that behaviour for