Summary:
This diff includes:
- progressive dimension k-means.
- the ResidualQuantizer object
- GpuProgressiveDimIndexFactory so that it can be trained on GPU
- corresponding tests
- reference Python implementation of the same in scripts/matthijs/LCC_encoding
Reviewed By: wickedfoo
Differential Revision: D27608029
fbshipit-source-id: 9a8cf3310c8439a93641961ca8b042941f0f4249
