tools: Print object metadata

Simple tool to print out an object's metadata

Change-Id: Ic2d79f28241fcf21b96c1245ef1d802e78710500
Signed-off-by: Luis Pabon <lpabon@redhat.com>
Reviewed-on: http://review.gluster.org/5386
Reviewed-on: http://review.gluster.org/5492