* Stocks rebound as investors snap up beaten-down shares* Ruble falls again after rate hike to 17 percent* Moscow stocks plunge, crude trades below $60 a barrel(Adds oil price settlement)By Herbert LashNEW YORK, Dec 16 (Reuters) - Oil prices pared losses and global equity markets rebounded on Tuesday as investors snapped up beaten-down energy stocks and wagered the U.S. central bank will express c