Build with newer Boost. From Fedora.

Index: gr-qtgui/lib/edit_box_msg_impl.cc
--- gr-qtgui/lib/edit_box_msg_impl.cc.orig
+++ gr-qtgui/lib/edit_box_msg_impl.cc
@@ -35,6 +35,8 @@
 namespace gr {
 namespace qtgui {
 
+using namespace boost::placeholders;
+
 edit_box_msg::sptr edit_box_msg::make(data_type_t type,
                                       const std::string& label,
                                       const std::string& value,
