docs: function parse_RgceLoc(blob, length, opts) {
  	if(opts && opts.biff >= 2 && opts.biff <= 5) return parse_RgceLoc_BIFF2(blob, length, opts);
  	var r = blob.read_shift(opts && opts.biff == 12 ? 4 : 2);
  	var c = parse_ColRelU(blob, 2);
  	return {r:r, c:c[0], cRel:c[1], rRel:c[2]};
  }