It�s musical chairs time at the MTC Biltmore. Theresa Rebeck�s new play Mauritius, her debut on Broadway, is one of those roundelays in which each of the five characters is trying to screw the others out of his/her interest in some very rare objects (here, postage stamps) and the whole thrust of the show is to find out which one(s) will be standing when the music stops and the final curtain falls.It is tightly plotted and full of the kind of snappy dialogue that one is familiar with from TV...