Update webots_ros to work webots_ros2 way

[BarceloChristian]

Hi!

I was wondering if there's any reason why webots_ros is not structured the same way webots_ros2. Mainly the import of devices through the </webots> in the URDF.

Is it just because the effort is put into ROS 2, or there's any other reason I'm not seeing?
If so, would a contribution to this repository to replicate its usage be welcomed?

[omichel]

Yes, we are putting our effort mainly on ROS 2 and only maintain the ROS 1 interface minimally. A contribution to this repository is always welcome, as long as it doesn't implies extra work for us, except for the review.