268381 Use after free in umlwidgets/diagramproxywidget.cpp
- In function slotMenuSelection case ListPopupMenu::mt_State_Diagram,
  if `ok` is true after the do-while loop then
  - assign d->view()->umlScene() to local variable `scene` before call
    to UMLApp::app()->executeCommand(d);
  - at calls to setDiagramLink and setWidgetLink use local `scene` in
    lieu of d->view()->umlScene().
    Reason: `d` may have been invalidated by the executeCommand call.

364153 Uninitialized scalar variable in dialogs/pages/
                                                selectoperationpage.cpp
- In copy constructor initialize m_enableAutoIncrement to false.
- In function slotAutoIncrementChecked assign `state` to
  m_enableAutoIncrement.
- As a related fix, in dialogs/selectoperationdialog.cpp function
  slotAutoIncrementChecked assign `state` to m_enableAutoIncrement.

364158 Resource leak in docgenerators/docbookgeneratorjob.cpp
- In function xsltprocExternalEntityLoader split the statement
        if (newURL != NULL && defaultEntityLoader != NULL) {
  into two statements
        if (newURL != NULL) {
            if (defaultEntityLoader != NULL) {
  such that xmlFree(newURL) is called regardless of the second
  condition.

Thanks to Ralf H. for updating https://github.com/rhabacker/umbrello

CCBUG: 340646