IDP-616

[Cantor, Scott]

Sorry for all the time wasted on this, it was completely trivial to fix in 
the storage plugin once I added the method to the sealer API.

Left open for Ian to test, but it's ready to go.

I didn't wire up the detection logic in the short-lived storage for things 
like sessions, because those are unlikely to break and don't matter much 
if they do. We could if it's desirable, but probably isn't.

-- Scott