Use of deprecated Bind placeholders

Some of the Boost.Python headers still use the deprecated Bind placeholders in the global namespace:

> /usr/include/boost/bind.hpp:41:1: note: #pragma 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.

Fix the files:
-
-

with fixes:
1. Replace and with
2. Replace (global) `_1` with `boost::placeholders::_1`
3. Replace (global) `_2` with `boost::placeholders::_2`