added log message when opening any url

@@ -806,6 +806,7 @@ Casper.prototype.open = function open(location, settings) {
         }
     }
     this.emit('open', this.requestUrl, settings);
+    this.log(f('opening url: %s, HTTP %s', this.requestUrl, settings.method.toUpperCase()), "debug");
     this.page.openUrl(this.requestUrl, {
         operation: settings.method,
         data:      settings.data