Revert "remove ml_classifieres from depend"

This reverts commit 849f4fcf0eeb7e8d248fc95e4f40e56b82b89f60.
Revert "Trimmed the branch to only the 3rdparty/sklearn sub directory"

This reverts commit 138dd9536c51a0d09ec3a433cefaf4d0e0b9a250.
Rebase from 'upstream'
Trimmed the branch to only the 3rdparty/sklearn sub directory
remove ml_classifieres from depend