v2v: -o rhev: Use chown --reference instead of 36.36 (RHBZ#1143887).

When chowning the final directories, instead of chowning them to 36.36
(ie. hard-coding those UID/GIDs), use a --reference chown so it should
take the ownership from the parent directory.

Unfortunately chowning is very complex because of:

 - NFSv3 vs NFSv4

 - root squash

 - idmap

which creates approximately 8 different ways for this to fail.