streaming → mathematics 关系

文件在 src/shogun/features/streaming	在 src/shogun/mathematics 中引用
StreamingDenseFeatures.cpp	Math.h
StreamingHashedDocDotFeatures.cpp	Math.h
StreamingSparseFeatures.h	Math.h
StreamingStringFeatures.h	Math.h
StreamingVwFeatures.h	Math.h