Revert "remove ml_classifieres from depend"

This reverts commit 49dd1f4b58bc64fa713bbb7be9efed62c05d5f57.
Revert "Trimmed the branch to only the 3rdparty/sklearn sub directory"

This reverts commit 2bee545182a8b9202a6ed99c69c4311c668cead4.
Rebase from 'upstream' (no changes)
Trimmed the branch to only the 3rdparty/sklearn sub directory
remove ml_classifieres from depend