CopyTool

using UnityEngine;
using UnityEditor;
using System.Collections;
using System.IO;

public class CopyTool : Editor {

public string sourcePath = string.Empty;
public string targetPath = string.Empty;

public void Copy()
{
//Now Create all of the directories
foreach (string dirPath in Directory.GetDirectories(sourcePath, "*",
SearchOption.AllDirectories))
Directory.CreateDirectory(dirPath.Replace(sourcePath, targetPath));

//Copy all the files
foreach (string newPath in Directory.GetFiles(sourcePath, "*.*",
SearchOption.AllDirectories))
File.Copy(newPath, newPath.Replace(sourcePath, targetPath), true);

Debug.Log("Copied all");
}
}