message: rtabmap.launch: fixed gen_cloud_from_depth nodelet wrongly started when gen_cloud is false
diff: </group>
  </group>
  - <node pkg="nodelet" type="nodelet" name="gen_cloud_from_depth" args="standalone rtabmap_ros/point_cloud_xyz" clear_params="$(arg clear_params)" output="$(arg output)">
  + <node if="$(arg gen_cloud)" pkg="nodelet" type="nodelet" name="gen_cloud_from_depth" args="standalone rtabmap_ros/point_cloud_xyz" clear_params="$(arg clear_params)" output="$(arg output)">
  <remap from="depth/image" to="$(arg depth_topic_relay)"/>
  <remap from="depth/camera_info" to="$(arg camera_info_topic)"/>
  <remap from="cloud" to="$(arg scan_cloud_topic)" />
  