bugfix for newer versions of node: fs.writeFile

Some later versions of node are not happy when fs.writeFile has an
empty call back.

Signed-off-by: Yefu Wang <m@yefu.org>

lib/localFileServer.js

@@ -74,7 +74,7 @@
                     thisObj.log("Loading from parent " );
                     thisObj.parent.load(fileName, function(cont){
                         thisObj.mkdirP(path.dirname(localfileResized));
-                        fs.writeFile(localfileResized, cont); // Possible thread collision!
+                        fs.writeFile(localfileResized, cont, function(){}); // Possible thread collision!
                         onSuccess(cont);
                     }, onError)
                 }