adapt Tendermint to new abci.Client interface

which was introduced in https://github.com/tendermint/abci/pull/130

mempool/mempool_test.go

@@ -172,13 +172,19 @@ func TestSerialReap(t *testing.T) {
 		for i := start; i < end; i++ {
 			txBytes := make([]byte, 8)
 			binary.BigEndian.PutUint64(txBytes, uint64(i))
-			res := appConnCon.DeliverTxSync(txBytes)
-			if !res.IsOK() {
+			res, err := appConnCon.DeliverTxSync(txBytes)
+			if err != nil {
+				t.Errorf("Client error committing tx: %v", err)
+			}
+			if res.IsErr() {
 				t.Errorf("Error committing tx. Code:%v result:%X log:%v",
 					res.Code, res.Data, res.Log)
 			}
 		}
-		res := appConnCon.CommitSync()
+		res, err := appConnCon.CommitSync()
+		if err != nil {
+			t.Errorf("Client error committing: %v", err)
+		}
 		if len(res.Data) != 8 {
 			t.Errorf("Error committing. Hash:%X log:%v", res.Data, res.Log)
 		}