(Removes extraneous "as" in headline, no other change to text) By Chibuike Oguh and Sara Rossi NEW YORK/LONDON (Reuters) - An index of world equity markets edged higher in choppy trading after hitting a record high on Tuesday ahead of the widely expected start of the Federal Reserve's interest rate cutting cycle, while U.S. Treasury yields and the dollar fell. MSCI's all-country index was a shade higher by 0.04% after rising as far as 978.74, a record high. Wall Street stocks erased earlier session gain ...