Deprecate historical proofs in eth_getProof API.

[darioush]

• Add a boolean VM configuration option like historical-proofs which defaults to false.
• In the API layer, reject calls to eth_getProof for blocks before latest - tipBufferSize, this is because with a path based trie, there is no good way to recall historical trie nodes and storing these nodes is a burden for validators. For most use cases (eg, message passing) it should suffice to verify state near the head of the chain, as often these use cases are time-sensitive.

Additional considerations / discussion topics:

• Entities with an interest in maintaining historical proofs can maintain their own indexes or use the hash db and modify the config option from its default.
• We can make the config option an integer which also controls tipBufferSize, which will also need to match the in-memory layers we keep at tip for the pathdb.
• Should we consider an upstream PR?