message: Adds panda arm back to arm hand urdf.
diff: <robot xmlns:xacro="http://www.ros.org/wiki/xacro" name="panda">
  <xacro:include filename="$(find franka_description)/robots/panda_arm.xacro"/>
  <xacro:include filename="$(find franka_description)/robots/hand.xacro"/>
  + <xacro:panda_arm/>
  <xacro:hand ns="panda" rpy="0 0 ${-pi/4}" connected_to="panda_link8"/>
  </robot>
  