Resource store loses historic values as events expire #11
Description
If a DERControl completes, it's typically removed from the DERControlList - this means a future discovery will delete it from the resource store.
Unfortunately, some actions (such as responding to DERControl saying that it has completed execution) need a way to see that a DERControl did once live on the server DERControlList and that an action (sending a completed Response) needs to still take place.
Need a way for resource store clearing to push the cleared resources into an archive. Also need a way for an action to query for archived versions of a particular resource type (organised by each resource's unique ID - as discussed at #10)