extras/hook-scripts: Set of changes for new samba share method.

New method of creating a share of gluster volume
through samba eliminates the requirement of fuse
mount and changes in fstab.

glusterfs vfs plugin has to be specified as required
vfs object.
Path now is relative to the root of gluster volume.
/ signifies complete volume.

Change-Id: I3d80452cd58513ef59d6a816c1ab62ebc3b76a62
BUG: 953694
Signed-off-by: Raghavendra Talur <rtalur@redhat.com>
Reviewed-on: http://review.gluster.org/5247
Reviewed-by: José Rivera <jrivera@redhat.com>
Tested-by: José Rivera <jrivera@redhat.com>
Reviewed-by: Vijay Bellur <vbellur@redhat.com>