additionally.c and box.c

[Thilanka97]

@AlexeyAB other than calibrating to find multipler values for each layer, did you do any other methods to support or make yolo work with int8 data? What happens in additionally.c and box.c ? why do you use a different box.c ? and do you use methods and techniques in additionally.c to make yolo work with 8bits?

Thanks in advance!