Pullup changes to trunk for RC2. Includes drag-fires click changes

(Closes #982), comment/documentation/requires changes (Closes #983, #993, #988),
Fixing post support in proxy.cgi (Closes #991), baseLayer zoom level change 
(Closes #990), typo in Layer.Image.setURL (Closes #985), and a fix or the
Layer.Google bug caused by Google's changing internals (#994). RC2, here we 
come.


git-svn-id: http://svn.openlayers.org/branches/openlayers/2.5@4390 dc9f47b5-9b13-0410-9fdd-eb0c1a62fdaf

lib/OpenLayers/Handler/Drag.js

@@ -253,13 +253,8 @@ OpenLayers.Handler.Drag = OpenLayers.Class(OpenLayers.Handler, {
      * {Boolean} Let the event propagate.
      */
     click: function (evt) {
-        // throw away the first left click event that happens after a mouse up
-        if (this.dragging) {
-            this.dragging = false;
-            return false; 
-        }
-        this.started = false;
-        return true;
+        // let the click event propagate only if the mouse moved
+        return (this.start == this.last);
     },
 
     /**