Revert "remove ml_classifieres from depend"

This reverts commit 44d2dc580649e82a5a3c186573f91bfb38ee8b18.
Revert "Trimmed the branch to only the 3rdparty/sklearn sub directory"

This reverts commit afa38c4a78b7af0d9f45326925ae80a4952df46e.
Rebase from 'upstream'
Trimmed the branch to only the 3rdparty/sklearn sub directory
remove ml_classifieres from depend