Add a "validated" entry in the full Ledger's Json.

Reviewers:
  @JoelKatz @donovanhide

This is in response to "blocker" RIPD-698.
Whoa.  Somehow I missed this (I did this fast because it's urgent).  Several things wrong with that code.  For one, we should never set validated to be false (because we never know for sure if a ledger is NOT validated).

Let me fix that, moment pls...!