add a requires on parent class, ND comments fixes

git-svn-id: http://svn.openlayers.org/trunk/openlayers@7882 dc9f47b5-9b13-0410-9fdd-eb0c1a62fdaf

lib/OpenLayers/Renderer/Canvas.js

@@ -2,10 +2,16 @@
  * license.  See http://svn.openlayers.org/trunk/openlayers/license.txt for the
  * full text of the license. */
 
+/**
+ * @requires OpenLayers/Renderer.js
+ */
+
 /**
  * Class: OpenLayers.Renderer.Canvas 
  * A renderer based on the 2D 'canvas' drawing element.element
  * 
+ * Inherits:
+ *  - <OpenLayers.Renderer>
  */
 OpenLayers.Renderer.Canvas = OpenLayers.Class(OpenLayers.Renderer, {
 
@@ -36,7 +42,7 @@ OpenLayers.Renderer.Canvas = OpenLayers.Class(OpenLayers.Renderer, {
     geometryMap: null,
  
     /**
-     * Constructor: OpenLayers.Renderer 
+     * Constructor: OpenLayers.Renderer.Canvas
      *
      * Parameters:
      * containerID - {<String>}