LU-611 utils: add restripe option to lfs_migrate

LU-611 utils: add restripe option to lfs_migrate

Add the "-R" option to have lfs_migrate restripe a migrated file
instead of keeping the original striping.  This is useful of some
directory got the wrong striping and a bunch of files were created
with the wrong striping.

Avoid possible confusion between the lfs_migrate and lfs setstripe
command-line options.  For now, deprecate the old "-c" option, since
it is redundant in any case.

Change-Id: I3a39bad93ef5c079678c65960e53d22e51431df3
Signed-off-by: Andreas Dilger <adilger@whamcloud.com>
Reviewed-on: http://review.whamcloud.com/1265
Tested-by: Hudson
Tested-by: Maloo <whamcloud.maloo@gmail.com>
Reviewed-by: Yu Jian <yujian@whamcloud.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>