Nest some more namespaces

Did someone previously suggest that all namespace had been
nested?  Silly.

Signed-off-by: Stephan Pleines <pleines.stephan@gmail.com>
Change-Id: I22278c1caaeba8b47dc46fb2ed3078c20a11e190
diff --git a/frc971/control_loops/flywheel/flywheel_controller.h b/frc971/control_loops/flywheel/flywheel_controller.h
index db8baeb..49a4385 100644
--- a/frc971/control_loops/flywheel/flywheel_controller.h
+++ b/frc971/control_loops/flywheel/flywheel_controller.h
@@ -9,9 +9,7 @@
 #include "frc971/control_loops/hybrid_state_feedback_loop.h"
 #include "frc971/control_loops/state_feedback_loop.h"
 
-namespace frc971 {
-namespace control_loops {
-namespace flywheel {
+namespace frc971::control_loops::flywheel {
 
 class CurrentLimitedStateFeedbackController;
 
@@ -73,8 +71,6 @@
   DISALLOW_COPY_AND_ASSIGN(FlywheelController);
 };
 
-}  // namespace flywheel
-}  // namespace control_loops
-}  // namespace frc971
+}  // namespace frc971::control_loops::flywheel
 
 #endif  // FRC971_CONTROL_LOOPS_SHOOTER_FLYWHEEL_CONTROLLER_H_