Clarification of ROLE_CIVIL

ROLE_CIVIL is supposed to represent "normal" traffic participants

Author: adrianschultz

osi_object.proto

@@ -971,7 +971,7 @@ message MovingObject
             //
             ROLE_AMBULANCE = 2;
 
-            // The vehicle role is civil.
+            // The vehicle role is civil, e.g. a "normal" car.
             //
             ROLE_CIVIL = 3;