Add default attribute :pavlov_options

[marten]

This was previously removed. I'd love to review for you, but why the reinstatement?

[markijbema]

We found that the changes needed in our code base became so large that it isn't possible anymore to review them anymore in github. Therefore we're trying to phase changes.

Also, I think it's bad to have this implicit first, then explicit, and then implicit again. Secondly, it's a rather weird split, it's explicitly mentioned in the attributes, but not in the helpers when calling other stuff. This feels rather asymmetric to me.

[marten]

In that case you probably want to remove the pavlov_options attribute declaration from the specs, so that it uses this automatically provided one.

[tomdev]

Good point.