How to launch nodelet? (RTABmap)

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Hi,

I came up across remote mapping and RTABmap provides this launch file:

<launch>
  <include file="$(find freenect_launch)/launch/freenect.launch">
     <arg name="depth_registration" value="True" />
  </include>

  <arg name="rate"  default="5"/>
  <arg name="approx_sync" default="true" /> <!-- true for freenect driver -->

  <!-- Use same nodelet used by Freenect/OpenNI -->
  <group ns="camera">
    <node pkg="nodelet" type="nodelet" name="data_throttle" args="load rtabmap_ros/rgbd_sync camera_nodelet_manager" output="screen">
      <param name="compressed_rate"  type="double" value="$(arg rate)"/>
      <param name="approx_sync"      type="bool"   value="$(arg approx_sync)"/>

      <remap from="rgb/image"       to="rgb/image_rect_color"/>
      <remap from="depth/image"     to="depth_registered/image_raw"/>
      <remap from="rgb/camera_info" to="rgb/camera_info"/>

      <remap from="rgbd_image"      to="rgbd_image"/>
    </node>
  </group>      
</launch>

What is the camera_nodelet_manager and how can I supply it? For example, if I use ZED camera they supply with the camera_manager: https://github.com/stereolabs/zed-ros...

But how exactly can I use it?