[Call for Test] unionfs intermediate umount feature

Hi unionfs users ;)

We have developed new unionfs feature, "intermediate umount".
You can do like this:

  # mount_unionfs /test2 /test1
  # mount_unionfs /test3 /test1
  # df
  <above>:/test2  xxxxx xxxxx xxxxx  xx%  /test1
  <above>:/test3  xxxxx xxxxx xxxxx  xx%  /test1
  # umount '<above>:/test2'
  # df
  <above>:/test3  xxxxx xxxxx xxxxx  xx%  /test1
  #

patch for current:
    http://people.freebsd.org/~daichi/unionfs/experiments/unionfs-intermediate-umount.diff

First, I want to know your opinion. Thanks :)

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Daichi GOTO