GLOBAL MARKETS-Stress tests, Ebola cool stocks after best week of year

* Stocks dip but head for best week of the year* Risk sentiment hit by first Ebola case in NY* U.S. and euro zone economic data positive* Oil on track for first weekly gain in five weeksBy Marc JonesLONDON, Oct 24 (Reuters) - World stocks dipped on Friday, as European bank stress test results due at the weekend and New York City&aposs first case of Ebola prompted investors to lock in profits after