load_object() - find or load an object by file name
object load_object( string str );
Find the object with the file name 'str'. If the file exists and the
object hasn't been loaded yet, it is loaded and returned (if possible).
load_object() returns the loaded object if it can be loaded (or already
loaded), otherwise the value 0 will be returned.
file_name(3), find_object(3), stat(3)