Documentation improvements provided by Glen Stampoultzis. (Thanks Glen!) Closes

#825, #836.


git-svn-id: http://svn.openlayers.org/trunk/openlayers@3728 dc9f47b5-9b13-0410-9fdd-eb0c1a62fdaf

lib/OpenLayers/Map.js

@@ -10,6 +10,10 @@
  * Class: OpenLayers.Map
  * Instances of OpenLayers.Map are interactive maps embedded in a web page.
  * Create a new map with the <OpenLayers.Map> constructor.
+ * 
+ * On their own maps do not provide much functionality.  To extend a map
+ * it's necessary to add controls (<OpenLayers.Control>) and 
+ * layers (<OpenLayers.Layer>) to the map. 
  */
 OpenLayers.Map = OpenLayers.Class.create();
 /**