Make it possible to change the filter in handlers

Trigger the 'select'-event earlier, this way any handlers for the event can
change both the filter and the resulting SLD inside the callback.

lib/OpenLayers/Control/SLDSelect.js

@@ -533,12 +533,13 @@ OpenLayers.Control.SLDSelect = OpenLayers.Class(OpenLayers.Control, {
                 }
     
                 var selectionLayer = this.createSelectionLayer(layer);
-                var sld = this.createSLD(layer, filters, geometryAttributes);
     
                 this.events.triggerEvent("selected", {
                     layer: layer,
                     filters: filters
                 });
+
+                var sld = this.createSLD(layer, filters, geometryAttributes);
     
                 selectionLayer.mergeNewParams({SLD_BODY: sld});
                 delete this._queue;