Save key and implement "all" function for the privateStore

[oed]

Right now we only store the value of the entry in the private store. We only use the hash of the key as the key in the private store. We can also store the key itself along with the value of the entry. This allows us to implement the all function for the private store as well. It should also be possible to do this in a backwards compatible way where only new entries will be visible in from the all function.