* Split deletePastBlocks into sub-routines
* Remove SelectedParentIterator, and refactor SelectedChildIterator to support First and Error
* Implement PruneAllBlocks
* Prune all blocks in the store
* Prune only blocks that are below the pruning point
* Defer call onEnd of LogAndMeasureExecutionTime
* Handle a forgotten error
* Minor style fixes
* [NOD-1528] Make data stores copy data on stage
* [NOD-1528] Add proto objects to serialize consensus state objects
* [NOD-1528] Fix receiver names
* [NOD-1528] Add copy to block store and utxo diff staging
* [NOD-1528] Return errors where needed