Summary:
This diff adds an object for a few useful dataset in faiss.contrib.
This includes synthetic datasets and the classic ones.
It is intended to work on:
- the FAIR cluster
- gluster
- manifold
Reviewed By: wickedfoo
Differential Revision: D23378763
fbshipit-source-id: 2437a7be9e712fd5ad1bccbe523cc1c936f7ab35
