batch importer

[hartsantler]

actually i'm getting an error from `wings_import:import(E3dFile, wpa:get_state()).`
the error is:

Code:

** exception error: no function clause matching
                    gb_trees:get_1(wings_shape,nil) (gb_trees.erl, line 244)
     in function  wings_shape:new/3 (wings_shape.erl, line 64)
     in call from wings_import:translate_objects/7 (wings_import.erl, line 46)
     in call from wings_import:import/2 (wings_import.erl, line 31)