Revert "remove ml_classifieres from depend"

This reverts commit 98161f0feae34a40e1bc44429f52e3c27c4dac85.
Revert "Trimmed the branch to only the 3rdparty/sklearn sub directory"

This reverts commit fcc6a75011b21645650d89728acc8a452f74a411.
Rebase from 'upstream'
Trimmed the branch to only the 3rdparty/sklearn sub directory
remove ml_classifieres from depend