enable onOp option to capture the changes old and new value

[gudipudipradeep]

enable onOp option to capture the changes of old and new value to analysis.

[gazedreamily]

The op is to represent a step what the value changes to. It is not a change process but an action.

[gudipudipradeep]

@gazedreamily in op we can able to see the changed value but not old value. Like Old: 5 New: 8 So that it will be clear to know for auditing and making some decision.