Negligence – Action upon the case – Limitation – Whether action statute-barred – Application to amend pleadings – Whether in interests of justice amendments should be allowed – Evidence – Expert witness – Application to rely upon expert evidence – Content of expert witness’s report – Limitation of Actions Act, 1881, section 46, Limitation Act, 21 Ja. I, c. 16, sections 3 and 7, Civil Procedure Rules, 2002, rules 11.6(1), 20.1, 20.4, 20.6, 32.2, 32.3, 32.4(2), 32.6(1), 32.12 and 32.13(3)(a), (b) and (c)