ROS2 Humble Update

[stephenadhi]

Hi, I know this package is not maintained much, but I hope this PR could help with running pedsim in ROS2. It would be nice if you could create a new branch for humble, the other ROS2 distros are reaching EOL soon.

Originally forked from previous ROS2 PRs (jginesclavero and ksatyaki)

• build fixed, warning errors resolved
• Syntax changed for ros2 humble - nodes, launch files, parameter handling
• scene_file and config_file now as launch file arguments in pedsim_simulator
• spawning of agents in gazebo using the pedsim_gazebo_plugin
• pedsim_xml_to_occ_map.cpp script to convert obstacles in the xml scenarios into maps
• add generated maps (.pgm and .yaml) from the above mentioned script

[stephenadhi]

Ready to use. Test with turtlebot3:

ros2 launch pedsim_gazebo_plugin gazebo_tb3_house_demo_launch.py