You could call it a Hanukkah miracle. Or the arrival of intelligent life from another planet. Last Saturday at 5 a.m., while the rest of us slept, megacollector Mera Rubell walked among us, hunting local art."If you were living in New York, you'd be pushing your work a lot harder," Mera says with firmness. "With all of the millions of dollars poured into museums here, why are artists so contained?"