ROS2 various QOL updates (preparing new binary release)

[matlabbe]

TODO:

• doublecheck if there is no regression for 3D LiDAR + deskewing. Add vlp16 example with IMU and/or T265 (if working on ros2).
  • https://github.com/introlab/rtabmap_ros/blob/master/rtabmap_examples/launch/test_velodyne_t265_deskewing.launch
  • https://github.com/introlab/rtabmap_ros/blob/master/rtabmap_examples/launch/test_velodyne_d435i_deskewing.launch
  • https://github.com/introlab/rtabmap_ros/blob/master/rtabmap_examples/launch/test_velodyne.launch
• Convert demo_husky.launch
• Convert demo_appearance_mapping.launch. Won't do: there is no point to this online. Camera node required for this has been pushed to rtabmap_legacy in ros1. I think if we create a new ROS node wrapper for Camera class of rtabmap, we may revive this example.
• Convert demo_find_object.launch
• Convert demo_multi-session_mapping.launch
• Convert demo_isaac_carter_navigation.launch: Won't do The lidar format cannot be easily used out-of-the-box do appropriately do deskewing with the current deskewing approach. The "assembled" 360 scans don't have timestamp offset field set in the point cloud for every point by default. More work to make a proper demo with lidar would need to be done. For a VSLAM demo using Isaac simulator, we may check to add it in the future (maybe at the same time than an integration demo with Isaac vslam nodes).
• Convert demo_robot_mapping.launch
• Convert demo_stereo_outdoor.launch
• Convert demo_unitree_quadruped_robot.launch : Won't do: the unitree gazebo example has not been ported to ros2. See also this repo (https://github.com/IntelligentRoboticsLabs/go2_robot) for go2 robot with nav2, though not available in sim yet.
• quadrupedal robots VSLAM demo: https://github.com/chvmp/champ: current issue: tf2::Buffer::lookupTransform seems blocking Listener's thread when subscribing to an image topic on high CPU load ros2/geometry2#727

Converting rosbag from ROS1 to ROS2: https://gitlab.com/ternaris/rosbags
Fixing leading slash in topic frames: https://github.com/cartographer-project/cartographer_ros/blob/master/cartographer_ros/scripts/remove_leading_slashes.py

Converted rosbags https://drive.google.com/drive/folders/1FMz-3xTI4-ouKxOUXlRvyty0jmaUL7iQ?usp=drive_link