发布message给其他包使用

https://answers.ros.org/question/65716/which-is-the-correct-way-to-install-header-files-in-catkin-packages/

http://docs.ros.org/api/catkin/html/howto/format2/building_libraries.html

http://wiki.ros.org/ROS/Tutorials/CreatingMsgAndSrv

http://wiki.ros.org/catkin/CMakeLists.txt#What_Does_find_package.28.29_Do.3F