private void writeDir(ApplicationFile dir, Path path, ApplicationFile.PathFilter filenameFilter) throws IOException {
            if ( ! dir.isDirectory()) return;
            for (ApplicationFile file : listFiles(dir, filenameFilter)) {
                String name = file.getPath().getName();
                if (name.startsWith(".")) continue; //.svn , .git ...
                if (file.isDirectory()) {
                    curator.create(path.append(name));
                    writeDir(file, path.append(name), filenameFilter);
                } else {
                    writeFile(file, path);
                }
            }
        }
Writes some application package files into ZK - see write(app).

@param app the application package to use as input.
@throws IOException if not able to write to Zookeeper
configserver/src/main/java/com/yahoo/vespa/config/server/deploy/ZooKeeperDeployer.java