Added tests for ITransactable support in VtoWriter.
Added tests for ITransactable support in VtoWriter.

tweakmy/dnp3-old,sentient-energy/emsw-opendnp3-mirror,cverges/dnp3,sentient-energy/emsw-opendnp3-mirror,sentient-energy/emsw-opendnp3-mirror,cverges/dnp3,gec/dnp3,tweakmy/dnp3-old,sentient-energy/emsw-opendnp3-mirror,cverges/dnp3,gec/dnp3,cverges/dnp3,tweakmy/dnp3-old,cverges/dnp3,cverges/dnp3,gec/dnp3,tweakmy/dnp3-old,cverges/dnp3,gec/dnp3,sentient-energy/emsw-opendnp3-mirror,sentient-energy/emsw-opendnp3-mirror,sentient-energy/emsw-opendnp3-mirror