Base: misc patches

Convenience macros/function (in Interpreter.h)

* FC_PY_GetObject/Callable(), look for callables in a python object,
  which will be used in future patch to improve performance in various
  python observer/features.

* pyCall(WithKeywords)(), helper function to invoke the callable

Matrix4D:

* hasScale(), check if there is any scale in the transformation. If so,
  further check if the scale is uniform or not. This will be used in
  future patch for Part::TopoShape to decide which type of transform to
  apply.

Placement:

* translate/rotate(), new convenience API

Rotation:

* isSame/multiVec(), new convenience API

Polygon2d:

* Intersect(), GetCenter(), new convenience API.

FlagToggler:

* New class for exception safe flag toggling, similar to StateLocker
  but with template (actually, FlagToggler is added earlier by me).

BitsetLocker:

* New class for exception manipulation of a std::bitset variable.

src/Base/MatrixPy.xml

@@ -34,6 +34,14 @@ Scale the matrix with the vector
         </UserDocu>
       </Documentation>
     </Methode>
+    <Methode Name="hasScale">
+      <Documentation>
+        <UserDocu>
+hasScale(tol=None)
+Return 0 is no scale factor, 1 for uniform scaling, -1 for non-uniform scaling.
+        </UserDocu>
+      </Documentation>
+    </Methode>
     <Methode Name="unity">
       <Documentation>
         <UserDocu>unity() - make this matrix to unity</UserDocu>