LUDOC-22 fix: lfs getstripe option and example fixes

LUDOC-22 fix: lfs getstripe option and example fixes

This patch corrects the documentation of the lfs getstripe options
that have been depricated:
--count => --stripe-count
--index => --stripe-index
--size => --stripe-size
--offset => removed, deprecated by stripe-index

The following options were added::
--mdt-index (previously only -M was documented)
--layout (previously missing)

A few example output areas were also updated to reflect the current
output from the command.

Signed-off-by: Joseph Gmitter <joseph.gmitter@intel.com>
Change-Id: Id1875afc7a724a8f495018cb9ddea215e94b8954
Reviewed-on: http://review.whamcloud.com/22408
Tested-by: Jenkins
Reviewed-by: Andreas Dilger <andreas.dilger@intel.com>