Nest all namespaces

The compiler supports this now.  We can type less going forward.
No functional changes.

Signed-off-by: Stephan Pleines <pleines.stephan@gmail.com>
Change-Id: I29d6fa4f9aacc0e381f1a7637294db0392466995
diff --git a/y2020/control_loops/superstructure/shooter/shooter.cc b/y2020/control_loops/superstructure/shooter/shooter.cc
index c400e34..2792205 100644
--- a/y2020/control_loops/superstructure/shooter/shooter.cc
+++ b/y2020/control_loops/superstructure/shooter/shooter.cc
@@ -9,10 +9,7 @@
 #include "y2020/control_loops/superstructure/finisher/finisher_plant.h"
 #include "y2020/control_loops/superstructure/finisher/integral_finisher_plant.h"
 
-namespace y2020 {
-namespace control_loops {
-namespace superstructure {
-namespace shooter {
+namespace y2020::control_loops::superstructure::shooter {
 
 Shooter::Shooter()
     : finisher_(
@@ -141,7 +138,4 @@
   return status_builder.Finish();
 }
 
-}  // namespace shooter
-}  // namespace superstructure
-}  // namespace control_loops
-}  // namespace y2020
+}  // namespace y2020::control_loops::superstructure::shooter
diff --git a/y2020/control_loops/superstructure/superstructure.cc b/y2020/control_loops/superstructure/superstructure.cc
index b7d57b4..f951791 100644
--- a/y2020/control_loops/superstructure/superstructure.cc
+++ b/y2020/control_loops/superstructure/superstructure.cc
@@ -4,9 +4,7 @@
 #include "aos/events/event_loop.h"
 #include "aos/network/team_number.h"
 
-namespace y2020 {
-namespace control_loops {
-namespace superstructure {
+namespace y2020::control_loops::superstructure {
 
 using frc971::control_loops::AbsoluteAndAbsoluteEncoderProfiledJointStatus;
 using frc971::control_loops::AbsoluteEncoderProfiledJointStatus;
@@ -313,6 +311,4 @@
   }
 }
 
-}  // namespace superstructure
-}  // namespace control_loops
-}  // namespace y2020
+}  // namespace y2020::control_loops::superstructure
diff --git a/y2020/control_loops/superstructure/superstructure_lib_test.cc b/y2020/control_loops/superstructure/superstructure_lib_test.cc
index 8b34fc9..950593e 100644
--- a/y2020/control_loops/superstructure/superstructure_lib_test.cc
+++ b/y2020/control_loops/superstructure/superstructure_lib_test.cc
@@ -28,10 +28,7 @@
 DEFINE_string(config, "y2020/aos_config.json",
               "Name of the config file to replay using.");
 
-namespace y2020 {
-namespace control_loops {
-namespace superstructure {
-namespace testing {
+namespace y2020::control_loops::superstructure::testing {
 
 namespace {
 constexpr double kNoiseScalar = 0.01;
@@ -1473,7 +1470,4 @@
                                            aos::Alliance::kBlue,
                                            aos::Alliance::kInvalid));
 
-}  // namespace testing
-}  // namespace superstructure
-}  // namespace control_loops
-}  // namespace y2020
+}  // namespace y2020::control_loops::superstructure::testing
diff --git a/y2020/control_loops/superstructure/turret/aiming.cc b/y2020/control_loops/superstructure/turret/aiming.cc
index 0b2c5f3..238beda 100644
--- a/y2020/control_loops/superstructure/turret/aiming.cc
+++ b/y2020/control_loops/superstructure/turret/aiming.cc
@@ -3,10 +3,7 @@
 #include "y2020/constants.h"
 #include "y2020/control_loops/drivetrain/drivetrain_base.h"
 
-namespace y2020 {
-namespace control_loops {
-namespace superstructure {
-namespace turret {
+namespace y2020::control_loops::superstructure::turret {
 
 using frc971::control_loops::Pose;
 using frc971::control_loops::aiming::RobotState;
@@ -197,7 +194,4 @@
   return builder.Finish();
 }
 
-}  // namespace turret
-}  // namespace superstructure
-}  // namespace control_loops
-}  // namespace y2020
+}  // namespace y2020::control_loops::superstructure::turret
diff --git a/y2020/control_loops/superstructure/turret/aiming_test.cc b/y2020/control_loops/superstructure/turret/aiming_test.cc
index b63d705..855f66a 100644
--- a/y2020/control_loops/superstructure/turret/aiming_test.cc
+++ b/y2020/control_loops/superstructure/turret/aiming_test.cc
@@ -7,11 +7,7 @@
 #include "y2020/constants.h"
 #include "y2020/control_loops/drivetrain/drivetrain_base.h"
 
-namespace y2020 {
-namespace control_loops {
-namespace superstructure {
-namespace turret {
-namespace testing {
+namespace y2020::control_loops::superstructure::turret::testing {
 
 class TeamNumberEnvironment : public ::testing::Environment {
  public:
@@ -259,8 +255,4 @@
   EXPECT_EQ(0.0, goal->goal_velocity());
 }
 
-}  // namespace testing
-}  // namespace turret
-}  // namespace superstructure
-}  // namespace control_loops
-}  // namespace y2020
+}  // namespace y2020::control_loops::superstructure::turret::testing