LU-11138 lfs: getstripe display certain mirror(s)

LU-11138 lfs: getstripe display certain mirror(s)

Add [!] --mirror-index=[+-]<index> | [!] --mirror-id=[+-]<id>
option for lfs getstripe to print the components of mirror(s)
relative to <index>-th mirror or components of mirror(s) relative
to the one with mirror ID of <id>.

Change-Id: I9ab8fd5faaea07b7567f88665e06ca71157cca67
Signed-off-by: Bobi Jam <bobijam@whamcloud.com>
Reviewed-on: https://review.whamcloud.com/32804
Tested-by: Jenkins
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>
Reviewed-by: Jinshan Xiong <jinshan.xiong@gmail.com>
Tested-by: Maloo <hpdd-maloo@intel.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>