add missing std:: namespace to build on Debian 10

src/Mod/Drawing/App/DrawingExport.cpp

@@ -81,6 +81,7 @@
 #include <Base/Vector3D.h>
 
 using namespace Drawing;
+using namespace std;
 
 TopoDS_Edge DrawingOutput::asCircle(const BRepAdaptor_Curve& c) const
 {

src/Mod/Part/App/Geometry2d.cpp

@@ -83,6 +83,7 @@
 #include <Mod/Part/App/Geom2d/OffsetCurve2dPy.h>
 
 using namespace Part;
+using namespace std;
 
 extern const char* gce_ErrorStatusText(gce_ErrorType et);
 

src/Mod/Raytracing/App/AppRaytracingPy.cpp

@@ -40,6 +40,8 @@
 #include <Mod/Part/App/TopoShapePy.h>
 #include <App/Application.h>
 
+using namespace std;
+
 
 namespace Raytracing {
 class Module : public Py::ExtensionModule<Module>

src/Mod/Raytracing/App/LuxFeature.cpp

@@ -38,6 +38,7 @@
 
 
 using namespace Raytracing;
+using namespace std;
 
 PROPERTY_SOURCE(Raytracing::LuxFeature, Raytracing::RaySegment)
 

src/Mod/Raytracing/App/RayFeature.cpp

@@ -36,6 +36,7 @@
 
 
 using namespace Raytracing;
+using namespace std;
 
 PROPERTY_SOURCE(Raytracing::RayFeature, Raytracing::RaySegment)
 

src/Mod/TechDraw/App/Cosmetic.cpp

@@ -61,6 +61,7 @@
 #include "Cosmetic.h"
 
 using namespace TechDraw;
+using namespace std;
 
 LineFormat::LineFormat()
 {

src/Mod/TechDraw/App/Geometry.cpp

@@ -80,6 +80,7 @@
 #include "Geometry.h"
 
 using namespace TechDraw;
+using namespace std;
 
 // Collection of Geometric Features
 Wire::Wire()