Bug Fix - #312 Changing one task changes another

- Added a warning when modifying recurring tasks, that all instances of
  that task may be modified.  When task confirms a bulk edit the
  recurrence is again indicated (thanks to Cory Donnelly).

src/Task.cpp

@@ -134,7 +134,7 @@ void Task::setEntry ()
 }
 
 ////////////////////////////////////////////////////////////////////////////////
-Task::status Task::getStatus ()
+Task::status Task::getStatus () const
 {
   return textToStatus (get ("status")); // No i18n
 }