Recurrence: Broke out handleUntil as a separate function

- This means until porocesing is no longer controlled by rc.recurrence, which
  was never intended.

src/commands/CmdCalendar.cpp

@@ -73,6 +73,7 @@ int CmdCalendar::execute (std::string& output)
     monthsPerLine = preferredMonthsPerLine;
 
   // Load the pending tasks.
+  handleUntil ();
   handleRecurrence ();
   auto tasks = context.tdb2.pending.get_tasks ();