Add tests

[kadishmal]

• [ ] Simulate a deadlock and a corresponding failure by writing via multiple clients. The driver should receive an error and be able to properly handle it.
• [ ] Simulate a CAS OOM by repeatedly inserting large data in the same transaction without committing. At last CAS should be killed by the CUBRID Broker. This kills the connection between the CAS and the driver. The driver should detect a socket error and be able to properly handle it.