LU-2430 mdd: add lfs mv to migrate inode.

LU-2430 mdd: add lfs mv to migrate inode.

Add lfs mv to migrate the individual inode from one MDT to
another MDT, and this function will only migrate inode layout
on MDT but not touch data object on OST.

lfs mv -M 1 /mnt/lustre/test1 #move test1 to MDT1.

The directory will be migrated from top to the bottom, i.e.
migrating parent first, then migrating the child.

Add migrate into sanity 17n to check on-disk format.

Add sanity 230(c,d,e,f) sanityn 80 to for migration.

Signed-off-by: wang di <di.wang@intel.com>
Change-Id: Ib4456a1db8909bd96260c67fff48922081948dcd
Reviewed-on: http://review.whamcloud.com/6662
Tested-by: Jenkins
Reviewed-by: Alex Zhuravlev <alexey.zhuravlev@intel.com>
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: John L. Hammond <john.hammond@intel.com>
Reviewed-by: Oleg Drokin <oleg.drokin@intel.com>