Torts — Premises liability — Slip and fall in restaurant — Limitation of actions — Amended complaint — Relation back — Where plaintiff filed suit against two defendants, but body of complaint included only a single count of negligence against one of the defendants, subsequent amended complaint which added a second count alleging that second defendant had purchased restaurant from first defendant and, by written agreement, assumed all debts, responsibilities, and all other obligations of the first defendant in existence of the time of and prior to the purchase related back to timely-filed original complaint — Second defendant’s participation in lawsuit from its inception belied any claim that it had no notice of original action and was surprised by amended complaint, was not given fair notice of general factual scenario, or had no connection to litigation prior to amendment — Trial court erred in dismissing amended complaint as time-barred