split ur5 model in unnamed robot element

ur5_description/urdf/robot.urdf.xacro → ur5_description/urdf/model.urdf.xacro

@@ -9,7 +9,7 @@ joint_direction = [-1, -1, 1, 1, 1, 1]
 mass = [3.7000, 8.3930, 2.2750, 1.2190, 1.2190, 0.1879]
 center_of_mass = [ [0, -0.02561, 0.00193], [0.2125, 0, 0.11336], [0.11993, 0.0, 0.0265], [0, -0.0018, 0.01634], [0, 0.0018,0.01634], [0, 0, -0.001159] ]
 -->
-<robot name="universal_robot">
+<robot>
 
   <property name="pi" value="3.14159265" />