show reference frames

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Unfortunately, not all the reference frames are viewable. In gazebo 2.2 and higher, if you select the View Center of Mass / Inertia from the View menu, then it will display pink boxes representing the size of a box of uniform density with equivalent mass properties, and green lines that represent the link frame. Also, you can View Joints to see axis frames for the joints. Please make a feature request on bitbucket if you need additional functionality.