Reduced number of parallel build tool executions on travis
Reduced number of parallel build tool executions on travis

OAkyildiz/walrus,OAkyildiz/walrus,RIVeR-Lab/walrus,RIVeR-Lab/walrus,OAkyildiz/walrus,RIVeR-Lab/walrus,OAkyildiz/walrus,OAkyildiz/walrus,RIVeR-Lab/walrus,RIVeR-Lab/walrus,RIVeR-Lab/walrus,OAkyildiz/walrus,OAkyildiz/walrus,RIVeR-Lab/walrus