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/CmdSummary.cpp

@@ -66,6 +66,7 @@ int CmdSummary::execute (std::string& output)
   bool showAllProjects = context.config.getBoolean ("summary.all.projects");
 
   // Apply filter.
+  handleUntil ();
   handleRecurrence ();
   Filter filter;
   std::vector <Task> filtered;