Implement the \x86 TUPLE2 opcode for decoding, operation 'Build a two-tuple

out of the top two items on the stack.'

ogórek.go

@@ -205,6 +205,8 @@ func (d Decoder) Decode() (interface{}, error) {
 			err = d.loadSetItem()
 		case opTuple:
 			err = d.loadTuple()
+		case opTuple2:
+			err = d.loadTuple2()
 		case opEmptyTuple:
 			d.push([]interface{}{})
 		case opSetitems:
@@ -607,6 +609,13 @@ func (d *Decoder) loadTuple() error {
 	return nil
 }
 
+func (d *Decoder) loadTuple2() error {
+	k := d.marker()
+	v := append([]interface{}{}, d.stack[k:]...)
+	d.stack = append(d.stack[:k], v)
+	return nil
+}
+
 func (d *Decoder) obj() error {
 	return errNotImplemented
 }