the cmakelist tutorial in wiki.ros for publisher/subscriber is not right
http://wiki.ros.org/ROS/Tutorials/Wri...
add_message_files, add_service_files, and generate_messages are not necessary for publisher/subscriber in cmakelist. Not to mention the appearance of AddTwoInts.srv... this whole page is about talk/listener. This must be messed up with the service/client version of cmakelist.