[Task] Remove/Move existing examples to other libraries

[bschifferer]

What needs doing Current existing examples are covering multiple concepts. They should be moved and/or removed.

Based on: https://docs.google.com/spreadsheets/d/1ncCGvDZtpUTbtI7VGZpJTk3RjcT5Ww9S_fr7YTF_yFw/edit#gid=0

• [ ] MovieLens
• [ ] Scaling Criteo
• [ ] Outbrain
• [ ] Winning RecSys2020
• [ ] mutli-gpu example
• [ ] multi-gpu movielens
• [ ] tensorflow

Additional context Add any other context, code examples, or references to existing implementations about the task here.