RelEx2Logic: temporary work-around for post-processing

Temporary work-around for post-processing code, assuming any R2L link that only contain one instanced word do not need post-processing, which is wrong, because you can have

```
EvaluationLink
    not
    run@1234
```

which do need to be include is post-processing.  Some new way is needed to classify the different type of R2L output.

Note: now create-abstract-version accept InterpretationNode.