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/CmdTimesheet.cpp

@@ -81,6 +81,7 @@ int CmdTimesheet::execute (std::string& output)
   }
 
   // Apply filter to get a set of tasks.
+  handleUntil ();
   handleRecurrence ();
   Filter filter;
   std::vector <Task> filtered;