Consolidate Unruly Adapter: Refactor

[marki1an]

No description provided.

[And1sS]

Also, could you please remove redundant ImpExtUnruly model and imp ext parsing? In go they just marshall and unmarshall to get rid of everything except imp.ext.bidder

it can be done, for example, this way:

private Imp modifyImp(Imp imp) {
        final ObjectNode modifiedExt = mapper.mapper().createObjectNode()
                .set("bidder", imp.getExt().get("bidder"));

        return imp.toBuilder().ext(modifiedExt).build();
    }