#include <boost/bind.hpp> is used instead of <boost/bind/bind.hpp> causing deprecation warning

The header files: fifo_worker.hpp and processor_container.hpp include instead of

During complication this causes the following warning:

message : The practice of declaring the Bind placeholders (_1, _2, ...) in the global namespace is deprecated. Please use + using namespace boost::placeholders, or define BOOST_BIND_GLOBAL_PLACEHOLDERS to retain the current behavior.

Remark: using may be a breaking change for projects that rely implicit on the fact that is used at the moment.