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/motors/peripheral/uart.h b/motors/peripheral/uart.h
index bfd630b..f8e7e7e 100644
--- a/motors/peripheral/uart.h
+++ b/motors/peripheral/uart.h
@@ -8,8 +8,7 @@
 #include "motors/peripheral/uart_buffer.h"
 #include "motors/util.h"
 
-namespace frc971 {
-namespace teensy {
+namespace frc971::teensy {
 
 // Simple synchronous interface to a UART.
 class Uart {
@@ -121,7 +120,6 @@
   UartBuffer<1024> transmit_buffer_, receive_buffer_;
 };
 
-}  // namespace teensy
-}  // namespace frc971
+}  // namespace frc971::teensy
 
 #endif  // MOTORS_PERIPHERAL_UART_H_