Inconsistency in parameter filter_by_coordinate_system

When refactoring some code for #410 I noticed that there is an inconsistency in the parameters. In filter_by_coordinate_system we pass on element_paths_in_coordinate_system to _filter_table_by_coordinate_system. However, looking at this function the argument here refers to coordinate_system.

Well spotted, the argument of _filter_table_by_coordinate_system() (and the function name), should be renamed.