* Brent Crude set for 16 pct drop in November* FTSEurofirst falls, led lower by oil & gas stocks* Euro zone inflation data at 1000 GMT; Bund pinned at lows* Dollar gains against commodity stocks, euro and yenBy Alistair SmoutLONDON, Nov 28 (Reuters) - Oil prices extended their recent slide on Friday, sending related shares and currencies lower, after OPEC decided to refrain from cutting output des