Update train_crop.py

[mouyuanyap]

Modify: int(xy) --> int(float(xy))

Solving this issue: Traceback (most recent call last): File "data/io/DOTA/train_crop.py", line 244, in box = format_label(txt_data) File "data/io/DOTA/train_crop.py", line 136, in format_label [int(xy) for xy in i.split(' ')[:8]] + [class_list.index(i.split(' ')[8])] File "data/io/DOTA/train_crop.py", line 136, in [int(xy) for xy in i.split(' ')[:8]] + [class_list.index(i.split(' ')[8])] ValueError: invalid literal for int() with base 10: '1786.0'