* 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
The rootdir in the distribution seems specific to the creators. I just made the rootdir for the fvecs be the suggested directory (sift1M) from the installation guide.