镜像恢复工具dd for windows

 dd for windows 是 Linux 下 dd 命令的 Windows ，可以做磁盘的块传输，例如将映像文件写入到磁盘或者U盘中。

使用方法：

dd [bs=SIZE[SUFFIX]] [count=BLOCKS[SUFFIX]] if=FILE of=FILE [seek=BLOCKS[SUFFIX]] [skip=BLOCKS[SUFFIX]] [--size] [--list] [--progress]

更新日志：

0.6beta3
========
- add errorlevel exit code
- progress is written to stderr

0.6beta2
========
- Implemented of=/dev/null which will just throw away the data
- skip on stdin now works
- fix checking size of floppy disks