Port assets_writer to ROS2

[chargerKong]

#47 Add assets_writer_node which can be called by

ros2 run cartographer_ros assets_writer_node \
-configuration_directory=xxx \
-configuration_basename=xxx.lua\
-bag_filenames=xxx\
-pose_graph_filename=xxx.pbstream\
-output_file_prefix=xxx\
-urdf_filename=xxx

where urdf_filename is optional

This code is tested in foxy, so I submit it to ros2 branch

[chargerKong]

Hi @clalancette, the CI error shows the packages "rosbag2_cpp" and "urdf" can not be found.

I’m not sure if the ROS index page, urdf and rosbag2_cpp has indicated that these two packages have been already been released in rolling

If so, should it be reinstalled, If not, which branch should I submit to?

[chargerKong]

Friendly ping @clalancette

[doisyg]

This can be probably closed as the asset_writer has also been ported in the recent v2 merge

[clalancette]

Yes, that is a good point. The only reason to keep this open would be to merge it onto the Galactic/Foxy branches. @chargerKong are you interested in having it there?