experimental → multibody Relation

File in drake/planning/experimental	Includes file in drake/multibody
mbp_environment_collision_checker.h	plant / multibody_plant.h
mbp_environment_collision_checker.h	tree / rigid_body.h
sphere_robot_model_collision_checker.h	plant / multibody_plant.h
sphere_robot_model_collision_checker.h	tree / rigid_body.h
voxel_self_filter.h	plant / multibody_plant.h
voxelized_environment_builder.h	plant / multibody_plant.h