* Add basic block/state caching on beacon chain
* Adds checkpoint cache
* Stop storing the tree hash cache in the db
* Remove dedunant beacon state write
* Use caching get methods in fork choice
* Use caching state getting in state_by_slot
* Add state.cacheless_clone
* Attempt to improve attestation processing times
* Introduce HeadInfo struct
* Used cache tree hash for block processing
* Use cached tree hash for block production too
