Rotates your images in the spirit of rot13

Its like rot13 but for images.
Calling the algorithm imrot10 for im = image, rot = rotation, 10 = default magnitude.
Unfortunately it is not symmetric like rot13 but i’m not wasting my time to develop fully symmetric so you have to use the -u parameter to undo it.
python3 image-rotator.py -h
usage: image-rotator.py [-h] [-i INPUT] [-o OUTPUT] [-u [UNDO]]
[--magnitude MAGNITUDE]
optional arguments:
-h, --help show this