FBGEMM based Int8 model - working with the master
1. Added int8 implementation into packed_gemm.h/cpp with FBGEMM
2. Update FBGEMM library to make it work on windows
3. Split 'ispacked' into packed8 and packed16
4. Change all names for PackFp32 to PackFp16 which is more accurate
minibatches are now fed in GPU-sized chunks rather than a massive joint batch for all GPUs in the update;
Adam hyper-parameter adjustment limited to learning rate, as momentum adjustment is counterproductive for MB scaling;
log output now includes the last batch size;
log output now shows current best for stalled validation metrics;
bug fix: Adam optimizer should persist denominators;
bug fix: Adam and Adagrad should use correct element size when persisting;
min and max renamed to minimum and maximum, for consistency with other toolkits;
pathie now compiles in manual VS Project
