Fix Placement.rotate() to match documentation

Documentation for Placement.rotate() claims this function would be
compatible to TopoShape.rotate() which isn't exactly correct as the
generated placements differ because of backwards multiplication.

This commit adds a "comp" (as in "compatible") keyword argument that -
when "True" (default is False) - produces a Placement that is interchangable with the one
that is generated from TopoShape.rotate().

src/Base/PlacementPyImp.cpp

@@ -163,22 +163,36 @@ PyObject* PlacementPy::translate(PyObject * args)
     return move(args);
 }
 
-PyObject* PlacementPy::rotate(PyObject *args) {
-    PyObject *obj1, *obj2;
+PyObject* PlacementPy::rotate(PyObject *args, PyObject *kw) {
     double angle;
-    if (!PyArg_ParseTuple(args, "OOd", &obj1, &obj2, &angle))
+    char *keywords[] =  { "center", "axis", "angle", "comp", nullptr };
+    Vector3d center;
+    Vector3d axis;
+    PyObject* pyComp = Py_False;
+    
+    if (!PyArg_ParseTupleAndKeywords(args, kw, "(ddd)(ddd)d|$O!", keywords, &center.x, &center.y, &center.z,
+                                         &axis.x, &axis.y, &axis.z, &angle, &PyBool_Type, &pyComp))
         return nullptr;
-
+    
     try {
-        Py::Sequence p1(obj1), p2(obj2);
-        Vector3d center((double)Py::Float(p1[0]),
-                        (double)Py::Float(p1[1]),
-                        (double)Py::Float(p1[2]));
-        Vector3d axis((double)Py::Float(p2[0]),
-                      (double)Py::Float(p2[1]),
-                      (double)Py::Float(p2[2]));
-        (*getPlacementPtr()) *= Placement(
-                Vector3d(),Rotation(axis,toRadians<double>(angle)),center);
+        /*
+         * if comp is False, we retain the original behaviour that - contrary to the documentation - generates
+         * Placements different from TopoShape.rotate() to ensure compatibility for existing code
+         */
+        bool comp = Base::asBoolean(pyComp);
+
+        if (!comp) {
+            (*getPlacementPtr()) *= Placement(
+                        Vector3d(),Rotation(axis,toRadians<double>(angle)),center);
+        } else 
+        {
+            // multiply new Placement the same way TopoShape.rotate() does
+        
+            Placement p = *getPlacementPtr();
+            *getPlacementPtr() = Placement(
+                        Vector3d(),Rotation(axis,toRadians<double>(angle)),center) * p;
+        }
+        
         Py_Return;
     }
     catch (const Py::Exception&) {