* Remove transitional print import.
* Add example for multiple GPUs in python.
* Add example on GPU in C++.
* Add example on multiple GPUs in C++.
* Add IVFFlat example on GPU in python.
* Add Makefile for C++ tutorial examples.
* Add IVF index on GPU example in C++.
* moved most FAISS_ASSERT calls to C++ exceptions, and adjusted
memory allocation to avoid mem leaks
* added an IndexIVFScalarQuantizer type that offers an
intermediate compression between IVFFlat and IVFPQ
* support removal of indices in IndexIDMap / IndexFlat combination
* various fixes in GPU code
* add initial cmake support
* update cmake, add cmake instructions to INSTALL
* update findopenmp and INSTALL
* change FindOpenBLAS.cmake to cater for macports
- change cblas.h to openblas_config.h since macports does not ship
cblas.h with openblas.
* revise INSTALL for cmake
Lucas Hosseini
Matthijs Douze
Tianwei Shen