Measure: modernize C++11

* use nullptr

src/Mod/Measure/App/AppMeasure.cpp

@@ -60,7 +60,7 @@ PyMOD_INIT_FUNC(Measure)
     }
     catch(const Base::Exception& e) {
         PyErr_SetString(PyExc_ImportError, e.what());
-        PyMOD_Return(0);
+        PyMOD_Return(nullptr);
     }
     PyObject* mod = Measure::initModule();
     // Add Types to module

src/Mod/Measure/App/MeasurementPyImp.cpp

@@ -60,7 +60,7 @@ PyObject* MeasurementPy::addReference3D(PyObject *args)
     char *ObjectName;
     char *SubName;
     if (!PyArg_ParseTuple(args, "ss:Give an object and subelement name", &ObjectName,&SubName))
-        return 0;
+        return nullptr;
 
     // get the target object for the external link
     App::DocumentObject * Obj = App::GetApplication().getActiveDocument()->getObject(ObjectName);
@@ -68,7 +68,7 @@ PyObject* MeasurementPy::addReference3D(PyObject *args)
         std::stringstream str;
         str << ObjectName << "does not exist in the document";
         PyErr_SetString(PyExc_ValueError, str.str().c_str());
-        return 0;
+        return nullptr;
     }
 
     // add the external
@@ -76,7 +76,7 @@ PyObject* MeasurementPy::addReference3D(PyObject *args)
         std::stringstream str;
         str << "Not able to add reference";
         PyErr_SetString(PyExc_ValueError, str.str().c_str());
-        return 0;
+        return nullptr;
     }
 
     Py_Return;
@@ -86,7 +86,7 @@ PyObject* MeasurementPy::has3DReferences(PyObject *args)
 {
     PyObject *result=Py_False;
     if (!PyArg_ParseTuple(args, ""))
-        return 0;
+        return nullptr;
 
     if (getMeasurementPtr()->has3DReferences()) {
         result = Py_True;
@@ -99,7 +99,7 @@ PyObject* MeasurementPy::has3DReferences(PyObject *args)
 PyObject* MeasurementPy::clear(PyObject *args)
 {
     if (!PyArg_ParseTuple(args, ""))
-        return 0;
+        return nullptr;
 
     this->getMeasurementPtr()->clear();
 
@@ -109,7 +109,7 @@ PyObject* MeasurementPy::clear(PyObject *args)
 PyObject* MeasurementPy::delta(PyObject *args)
 {
     if (!PyArg_ParseTuple(args, ""))
-        return 0;
+        return nullptr;
 
     Py::Vector delta(this->getMeasurementPtr()->delta());
 
@@ -119,7 +119,7 @@ PyObject* MeasurementPy::delta(PyObject *args)
 PyObject* MeasurementPy::length(PyObject *args)
 {
     if (!PyArg_ParseTuple(args, ""))
-        return 0;
+        return nullptr;
 
     Py::Float length;
     length = this->getMeasurementPtr()->length();
@@ -130,7 +130,7 @@ PyObject* MeasurementPy::length(PyObject *args)
 PyObject* MeasurementPy::radius(PyObject *args)
 {
     if (!PyArg_ParseTuple(args, ""))
-        return 0;
+        return nullptr;
 
     Py::Float radius;
     radius = this->getMeasurementPtr()->radius();
@@ -141,7 +141,7 @@ PyObject* MeasurementPy::radius(PyObject *args)
 PyObject* MeasurementPy::angle(PyObject *args)
 {
     if (!PyArg_ParseTuple(args, ""))
-        return 0;
+        return nullptr;
 
     Py::Float angle;
     angle = this->getMeasurementPtr()->angle();
@@ -152,7 +152,7 @@ PyObject* MeasurementPy::angle(PyObject *args)
 PyObject* MeasurementPy::com(PyObject *args)
 {
     if (!PyArg_ParseTuple(args, ""))
-        return 0;
+        return nullptr;
 
     Py::Vector com(this->getMeasurementPtr()->massCenter());
 
@@ -161,7 +161,7 @@ PyObject* MeasurementPy::com(PyObject *args)
 
 PyObject *MeasurementPy::getCustomAttributes(const char* /*attr*/) const
 {
-    return 0;
+    return nullptr;
 }
 
 int MeasurementPy::setCustomAttributes(const char* /*attr*/, PyObject* /*obj*/)