Added two tests for testing readwrite split router's ability to route read to master if in active transaction and to slave when outside transaction.

server/modules/routing/readwritesplit/test/test_transaction_routing2.sql

@@ -1,3 +1,11 @@
+USE test; 
 SET autocommit = 0; 
-SELECT @@in_transaction INTO @a;
-SELECT @a;
+START TRANSACTION; 
+CREATE TABLE IF NOT EXISTS myCity (a int, b char(20)); 
+INSERT INTO myCity VALUES (1, 'Milan'); 
+INSERT INTO myCity VALUES (2, 'London'); 
+COMMIT; 
+START TRANSACTION; 
+DELETE FROM myCity;
+SELECT COUNT(*) FROM myCity; -- read transaction's modifications from master
+COMMIT;