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/zeroing/zeroing.h b/frc971/zeroing/zeroing.h
index 5d5b6eb..8fe381d 100644
--- a/frc971/zeroing/zeroing.h
+++ b/frc971/zeroing/zeroing.h
@@ -20,8 +20,7 @@
 // TODO(pschrader): Watch the offset over long periods of time and flag if it
 // gets too far away from the initial value.
 
-namespace frc971 {
-namespace zeroing {
+namespace frc971::zeroing {
 
 template <typename TPosition, typename TZeroingConstants, typename TState>
 class ZeroingEstimator {
@@ -169,7 +168,6 @@
   bool error_ = false;
 };
 
-}  // namespace zeroing
-}  // namespace frc971
+}  // namespace frc971::zeroing
 
 #endif  // FRC971_ZEROING_ZEROING_H_