boost: [skip ci] fix for boost < 1.60

src/App/DocumentObserverPython.cpp

@@ -24,6 +24,7 @@
 #include "PreCompiled.h"
 
 #ifndef _PreComp_
+# include <boost_bind_bind.hpp>
 #endif
 
 #include "Application.h"

src/Gui/DocumentObserverPython.cpp

@@ -24,6 +24,7 @@
 #include "PreCompiled.h"
 
 #ifndef _PreComp_
+# include <boost_bind_bind.hpp>
 #endif
 
 #include "Application.h"

src/Mod/PartDesign/App/ShapeBinder.cpp

@@ -33,6 +33,7 @@
 #endif
 
 #include <unordered_map>
+#include <unordered_set>
 #include <boost/algorithm/string/predicate.hpp>
 
 #include <Base/Console.h>