GLOBAL MARKETS-ECB stimulus talk knocks euro, peripheral yields

* Investors position for more ECB stimulus in June* Lower-rated euro zone debt yields fall to record lows* Euro slips further against dollar* Portuguese bonds also boosted by S&P outlook upgradeBy Francesco CanepaLONDON, May 9 (Reuters) - Lower-rated euro zone bond yields fell to fresh record lows and the common currency slid further on Friday as investors positioned for more monetary stimulus fro