Revert "Use the stdlib's ref and cref function templates."

This reverts commit a237a31.

Rationale:

With `std::ref` instead of `boost::ref`, luabind related code fails at
runtime (I love the smell of dynamic languages burning to the ground).

This happens, because luabind hardcodes a reference wrapper predicate
via SFINA for `boost::reference_wrapper` (the type returned from
`boost::ref`), but fails do to so for stdlib facilities (`std::ref`
and `std::reference_wrapper`).

I don't even blame them, I would have done the same in the year 2010,
as the upsream package is basically unmaintained since freaking 5 years.

References:

- https://gist.github.com/daniel-j-h/c98c03b3d02f713d035e
- #1646
- https://github.com/luabind/luabind/blob/457f28ab5a0d6331409883348588b43e3a0bc944/luabind/detail/convert_to_lua.hpp#L4MC�$

extractor/extractor.cpp

@@ -59,7 +59,6 @@ SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 #include <atomic>
 #include <chrono>
 #include <fstream>
-#include <functional>
 #include <iostream>
 #include <thread>
 #include <unordered_map>
@@ -179,17 +178,17 @@ int extractor::run()
                             ++number_of_nodes;
                             luabind::call_function<void>(
                                 local_state, "node_function",
-                                std::cref(static_cast<const osmium::Node &>(*entity)),
-                                std::ref(result_node));
+                                boost::cref(static_cast<const osmium::Node &>(*entity)),
+                                boost::ref(result_node));
                             resulting_nodes.push_back(std::make_pair(x, result_node));
                             break;
                         case osmium::item_type::way:
                             result_way.clear();
                             ++number_of_ways;
                             luabind::call_function<void>(
                                 local_state, "way_function",
-                                std::cref(static_cast<const osmium::Way &>(*entity)),
-                                std::ref(result_way));
+                                boost::cref(static_cast<const osmium::Way &>(*entity)),
+                                boost::ref(result_way));
                             resulting_ways.push_back(std::make_pair(x, result_way));
                             break;
                         case osmium::item_type::relation:

extractor/restriction_parser.cpp

@@ -33,11 +33,12 @@ SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 #include "../util/osrm_exception.hpp"
 #include "../util/simple_logger.hpp"
 
+#include <boost/algorithm/string.hpp>
 #include <boost/algorithm/string/regex.hpp>
+#include <boost/ref.hpp>
 #include <boost/regex.hpp>
 
 #include <algorithm>
-#include <functional>
 
 namespace
 {
@@ -86,7 +87,7 @@ void RestrictionParser::ReadRestrictionExceptions(lua_State *lua_state)
         luabind::set_pcall_callback(&lua_error_callback);
         // get list of turn restriction exceptions
         luabind::call_function<void>(lua_state, "get_exceptions",
-                                     std::ref(restriction_exceptions));
+                                     boost::ref(restriction_exceptions));
         const unsigned exception_count = restriction_exceptions.size();
         SimpleLogger().Write() << "Found " << exception_count
                                << " exceptions to turn restrictions:";