demo_files non-existent anymore

[pieris98]

Hey @giandbt,
Thanks for your work on synboost.
I've tried to run inference and/or training in the past days.
There are several package incompatibility issues on newer GPUs/pytorch/apex due to old versions when the paper was created.

I then tried to run the colab notebook.
Unfortunately, the demo_files.tar from the lab's amazon storage doesn't exist anymore i.e. running:
wget --no-check-certificate 'https://dissimilarity.s3.eu-central-1.amazonaws.com/demo_files.tar' returns a 404.
I saw in #6 that you had uploaded them there back then.

Would it be possible to share some of the demo_files (e.g. onnx_models files) so the colab notebook can be run successfully?