Changes from Toru Tsuneyoshi for using Trash can when deleting files.

Changes from Toru Tsuneyoshi for using Trash can when deleting files.

	* files.el (backup-extract-version): Handle versioned directories.
	(trash-directory): New variable.
	(move-file-to-trash): New function.

	* cus-start.el (delete-by-moving-to-trash): Declare for custom.

        * lisp.h (Qdelete_file, Qdelete_directory): Declare extern.

        * fileio.c (delete_by_moving_to_trash, Qmove_file_to_trash): New vars.
        (syms_of_fileio): Initialize and export them.
        (Fdelete_directory, Fdelete_file): Optionally delete via trash.

        * w32fns.c (FOF_NO_CONNECTED_ELEMENTS): Define if not already.
        (Fsystem_move_file_to_trash): New function.
        (syms_of_w32fns): Export it to lisp.