"[The] dismissal of a party's pleadings for failure to respond to a discovery order is an extreme sanction which is warranted only where there exists a clear record of delay or contumacious conduct, and a lesser sanction would not better serve the interests of justice." Chelena v. Milton Fried Med. Clinic, 171 Ga. App. 580, 581 ( 320 S.E.2d 583) (1984). However, the wilful failure to comply with an order requiring the payment of attorney fees to an opposing party as reimbursement for his expenses expended in obtaining a discovery order has been held to warrant the imposition of such a sanction.