Revert "remove ml_classifieres from depend"

This reverts commit 3a6f08fdc73b74de20b2f5790fba5cec82f34ff7.
Revert "Trimmed the branch to only the 3rdparty/sklearn sub directory"

This reverts commit 9bbdf08d45d7cfb261983992d3d2d1db0323e6b6.
Rebase from 'upstream' (no changes)
Trimmed the branch to only the 3rdparty/sklearn sub directory
remove ml_classifieres from depend