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/frc971/wpilib/interrupt_edge_counting.cc b/frc971/wpilib/interrupt_edge_counting.cc
index 9b63b84..4fc2172 100644
--- a/frc971/wpilib/interrupt_edge_counting.cc
+++ b/frc971/wpilib/interrupt_edge_counting.cc
@@ -5,8 +5,7 @@
 #include "aos/realtime.h"
 #include "aos/time/time.h"
 
-namespace frc971 {
-namespace wpilib {
+namespace frc971::wpilib {
 
 void EdgeCounter::GatherPolledValue() {
   shadow_values_.polled_value = input_->Get();
@@ -103,5 +102,4 @@
   return true;
 }
 
-}  // namespace wpilib
-}  // namespace frc971
+}  // namespace frc971::wpilib