App/Gui: fix memory leaks:

+ add function to cleanup units and quantities in debug build
+ fix reference leak in PropertyVector::getPyPathValue()
+ fix reference leak in PropertyPlacement::getPyPathValue()
+ in InterpreterSingleton::init() use a static std::vector<wchar_t*> instead of a C array
  to free memory at program end
+ in MainWindow::closeEvent() explicitly delete all task watchers
+ in ReportOutputObserver constructor pass parent to QObject
+ in PropertyEditor destructor explicitly delete QItemEditorFactory

src/Gui/Application.cpp

@@ -450,7 +450,6 @@ Application::Application(bool GUIenabled)
 
         // PySide additions
         PySideUicModule* pySide = new PySideUicModule();
-        Py_INCREF(pySide->module().ptr());
         PyModule_AddObject(module, "PySideUic", pySide->module().ptr());
 
         ExpressionBindingPy::init_type();