Made nd6 maximum unicast solicitation messages configurable
Made nd6 maximum unicast solicitation messages configurable

MohamedSeliem/contiki,arurke/contiki,arurke/contiki,bluerover/6lbr,bluerover/6lbr,arurke/contiki,arurke/contiki,arurke/contiki,arurke/contiki,MohamedSeliem/contiki,bluerover/6lbr,bluerover/6lbr,MohamedSeliem/contiki,bluerover/6lbr,arurke/contiki,bluerover/6lbr,MohamedSeliem/contiki,MohamedSeliem/contiki,MohamedSeliem/contiki,bluerover/6lbr,MohamedSeliem/contiki