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/y2016/actors/autonomous_actor.cc b/y2016/actors/autonomous_actor.cc
index ffba99b..d784d51 100644
--- a/y2016/actors/autonomous_actor.cc
+++ b/y2016/actors/autonomous_actor.cc
@@ -14,8 +14,7 @@
 #include "y2016/queues/ball_detector_generated.h"
 #include "y2016/vision/vision_generated.h"
 
-namespace y2016 {
-namespace actors {
+namespace y2016::actors {
 using ::aos::monotonic_clock;
 using ::frc971::ProfileParametersT;
 namespace superstructure = y2016::control_loops::superstructure;
@@ -985,5 +984,4 @@
   return true;
 }
 
-}  // namespace actors
-}  // namespace y2016
+}  // namespace y2016::actors
diff --git a/y2016/actors/superstructure_actor.cc b/y2016/actors/superstructure_actor.cc
index d33b125..734512a 100644
--- a/y2016/actors/superstructure_actor.cc
+++ b/y2016/actors/superstructure_actor.cc
@@ -8,8 +8,7 @@
 #include "y2016/control_loops/superstructure/superstructure_goal_generated.h"
 #include "y2016/control_loops/superstructure/superstructure_status_generated.h"
 
-namespace y2016 {
-namespace actors {
+namespace y2016::actors {
 
 namespace chrono = ::std::chrono;
 
@@ -112,5 +111,4 @@
   WaitUntil(::std::bind(&SuperstructureActor::SuperstructureDone, this));
 }
 
-}  // namespace actors
-}  // namespace y2016
+}  // namespace y2016::actors
diff --git a/y2016/actors/vision_align_actor.cc b/y2016/actors/vision_align_actor.cc
index a31ac5d..f636ddf 100644
--- a/y2016/actors/vision_align_actor.cc
+++ b/y2016/actors/vision_align_actor.cc
@@ -16,8 +16,7 @@
 #include "y2016/control_loops/drivetrain/drivetrain_base.h"
 #include "y2016/vision/vision_generated.h"
 
-namespace y2016 {
-namespace actors {
+namespace y2016::actors {
 
 VisionAlignActor::VisionAlignActor(::aos::EventLoop *event_loop)
     : aos::common::actions::ActorBase<vision_align_action::Goal>(
@@ -88,5 +87,4 @@
   return true;
 }
 
-}  // namespace actors
-}  // namespace y2016
+}  // namespace y2016::actors