sensors/zones: place in namespace and cleanup

Signed-off-by: Patrick Venture <venture@google.com>
Change-Id: I527dbc8477a232945f696227a7b0b2adbee45175
diff --git a/experiments/drive.hpp b/experiments/drive.hpp
index 94e74f3..e1a4d2d 100644
--- a/experiments/drive.hpp
+++ b/experiments/drive.hpp
@@ -1,3 +1,8 @@
 #pragma once
 
+namespace pid_control
+{
+
 int driveMain(void);
+
+}