Relax pip package requirements (#345)

* Implementing mean pointwise l2 distance

* Make torch and torchvision flexible, limit pillow to compatible versions

Co-authored-by: freddy <[email protected]>

Author: holger-motional

setup/requirements.txt

@@ -7,11 +7,11 @@ motmetrics<=1.1.3
 numpy
 opencv-python
 pandas>=0.24
-Pillow
+Pillow<=6.2.1  # Latest Pillow is incompatible with current torchvision, https://github.com/pytorch/vision/issues/1712
 pyquaternion>=0.9.5
 scikit-learn
 scipy
 Shapely
-torch==1.4.0
-torchvision==0.5.0
+torch>=1.3.1
+torchvision>=0.4.2
 tqdm