Changes

*'''Particles ''' - the dynamic cargo (un)loading of grainhoppers added in 1.51. For this type the other required attributes are '''trailer_particle''', '''world_particle''', and '''material_path'''. For dynamic cargo data to be considered correct, you must be able to load it (world_particle), unload it (trailer_particle), and display a material on the cargo pile mesh inside the trailer (material_path).*'''Mover ''' - the dynamic cargo (un)loading of logger trailers added in 1.52. This type ignores all the particle attributes, the only attributes that are considered (but not required) are ''loading_sound'' and ''unloading_sound_default'', which is the sound emitted when the log loader places a pile of logs into the trailer.