Use custom robot collision padding in occupancy map shape padding

Currently you can only use one padding and scale value for all robot self-filtering. I have an application where the fingers and end effector should have no padding or scaling, but I'd like the rest of the robot to still have padding.

This change uses the same variable collision padding as set in the planning scene monitor for the perception pipeline. Does not change API because the new function parameters have default values.

This does break user's current ``sensors_rgbd.yaml`` files in that it will not longer use padding from there, but instead from ``paddings.yaml`` file.

I'd also be happy to create default configuration files for the Setup Assistant for these changes.
At this point, padding_ and scale_ are no longer used, right? If so, they should probably be removed from the class, as well as their get param call in the constructor.