tweak training units script to not show catkin_make output and remove build directory if present
tweak training units script to not show catkin_make output and remove build directory if present

ros-industrial/industrial_training,alex1818/industrial_training,alex1818/industrial_training,AustinDeric/industrial_training,Levi-Armstrong/industrial_training,ros-industrial/industrial_training,Levi-Armstrong/industrial_training,AustinDeric/industrial_training,Levi-Armstrong/industrial_training,gomezc/industrial_training,gomezc/industrial_training,geoffreychiou/industrial_training,geoffreychiou/industrial_training,gomezc/industrial_training,ros-industrial/industrial_training,alex1818/industrial_training,AustinDeric/industrial_training,gomezc/industrial_training,ros-industrial/industrial_training,geoffreychiou/industrial_training,Levi-Armstrong/industrial_training,gomezc/industrial_training,alex1818/industrial_training