Break tier_migrate_using_query_file() into a more manageable tier_migrate_link() and helpers. Change-Id: I5eb2d2cff9e7a2a2da567c3c4c2d53aab195f477 BUG: 1358296 Signed-off-by: Milind Changire <mchangir@redhat.com> Reviewed-on: http://review.gluster.org/14957 Smoke: Gluster Build System <jenkins@build.gluster.org> NetBSD-regression: NetBSD Build System <jenkins@build.gluster.org> CentOS-regression: Gluster Build System <jenkins@build.gluster.org> Reviewed-by: Dan Lambright <dlambrig@redhat.com>