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/y2017/wpilib_interface.cc b/y2017/wpilib_interface.cc
index 822c3f4..f1205f3 100644
--- a/y2017/wpilib_interface.cc
+++ b/y2017/wpilib_interface.cc
@@ -67,8 +67,7 @@
 using namespace frc;
 using std::make_unique;
 
-namespace y2017 {
-namespace wpilib {
+namespace y2017::wpilib {
 namespace {
 
 constexpr double kMaxBringupPower = 12.0;
@@ -549,7 +548,6 @@
 };
 
 }  // namespace
-}  // namespace wpilib
-}  // namespace y2017
+}  // namespace y2017::wpilib
 
 AOS_ROBOT_CLASS(::y2017::wpilib::WPILibRobot);