Refactor Package Structure

[lukicdarkoo]

Description
This aims to improve the structure of the packages, by renaming, deleting unnecessary code and adding proper documentation before it is released:

• Now we have epuck_ros2_cpp but it should be language agnostic, so I think it should be renamed to epuck_ros2_driver
• There is a Python implementation of the driver in epuck_ros2. That implementation doesn't implement as many features as in epuck_ros2_cpp and we have much better performances with epuck_ros2_cpp. To avoid maintaining the code and not to create confusion I think this should be deleted.
• epuck_ros2 should depend on epuck_ros2_cpp and epuck_ros2_camera, and it should provide a mechanism to launch nodes from these packages.

Related Issues
Fixes #9
Also, this is related to this PR: cyberbotics/webots_ros2#69

Tasks

• Rename epuck_ros2_cpp to epuck_ros2_driver
• Delete Python driver implementation from epuck_ros2
• Create launch file in epuck_ros2 that is able to run nodes from epuck_ros2_driver and epuck_ros2_camera
• Add documentation
• epuck_ros2 does not depends on epuck_ros2_camera and epuck_ros2_camera is ignored. This has to be resolved
  • Exclude MMAL related files from build process in CI (if -DAVOID_EPUCK_CAMERA_BUILD is defined MMAL will be excluded from the build process, otherwise no changes)
  • As epuck_ros2_camera is now part of code quality verification resolve linter errors
• Verify if everything works on Raspberry Pi

Additional Context
ROS2 installation tutorial will be properly written later with #18.

For organizing documentation I followed this package:

• short documentation in the repo root, with CI and references to more thoughtful documentation,
• in the main package (epuck_ros2 in our case) there is no README,
• every other package has a short explanation and
• most of the documentation is located on the external website.

Building the packages in development on RPi:

colcon build --packages-select epuck_ros2 epuck_ros2_driver epuck_ros2_camera --cmake-args -DBUILD_TESTING:BOOL=OFF

[DavidMansolino]

Documentation check only for now.

[DavidMansolino]

Looks globally very good, just minor cleanups.

[DavidMansolino]

Thank you.