Two small cleanups and the offer->ACCOUNT->offer fix

1) When pathfinding, don't output a redundant account node.
This node serves no purpose because expandPath adds the node anyway. It's just a waste of bandwidth and space.

2) Cleanup some stray formatting
Obviously-correct cleanup.

3) Fix offer->ACCOUNT->offer

CAUTION: The third change affects transaction processing and requires planning and coordination in deployment. It should probably be combined with other transaction processing changes. (tefDST_TAG_NEEDED, for example.)
Even if there is no move support, this logic is much clearer, and the cost of copying these tiny items is tiny.

When we do enable move construction later, we'll therefore be getting extra value from it!

But of course, it's your call...