Reimplement transactions in cache manager / fasterkv

[JessicaMulein]

• Got writer's block/health issues for a bit. Recently got unstuck. Things are in an-inbetween state while I work through this nebulous ticket.
  • I have no contributors. If there's interest in more insight into what I'm doing please like or comment I'll happily explain my goals.
• Update: A fair chunk of BrightChain's Engine is moving to NeuralFabric which I'm going to let autonomously take care of the replication and serialization/fasterKV aspects, so BrightChain will no longer use FasterKV directly- NeuralFabric will.

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• Part one is getting back down to a single faster KV log/object device pair.
  • Now being completed in / blocked by Split out FasterKV into Neural, re-implement cachemanager with faster/neural abstracted. #8
• Part two is making the key a string and the value a binary blob.
• part three is making a class hierarchy to do the ser/deser into the faster kv between the block classes and the raw data blobs
• part four is to make sure simple blocks commit successfully to the data store and make proper use of the builtin commit/checkpoint/rollback features.
• part five is to make sure CBLs and SCBLs and everything all commit and that all block sizes sort out into CBL/SCBL properly.
  ... and so on..