Fixed ugly function pointer cast by implementing a wrapper function for the protothread function.
Fixed ugly function pointer cast by implementing a wrapper function for the protothread function.

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