Revert "remove ml_classifieres from depend"

This reverts commit 0d52e6c9cea99649b23efa266f57271f1d8f4377.
Revert "Trimmed the branch to only the 3rdparty/sklearn sub directory"

This reverts commit 4b9c558f7918df357e25171fc1e67e7167124891.
Rebase from 'upstream' (no changes)
Trimmed the branch to only the 3rdparty/sklearn sub directory
remove ml_classifieres from depend