Revert "remove ml_classifieres from depend"

This reverts commit 227d689cc6ceda0a05be4c99deb64eb66c6247d9.
Revert "Trimmed the branch to only the 3rdparty/sklearn sub directory"

This reverts commit b8287db2ffa0a2e2bebdb2ee6949b08f1f242e26.
Rebase from 'upstream'
Trimmed the branch to only the 3rdparty/sklearn sub directory
remove ml_classifieres from depend