Faster attestation production (#838)

* Start adding interop genesis state to lcli

* Use more efficient method to generate genesis state

* Remove duplicate int_to_bytes32

* Add lcli command to change state genesis time

* Add option to allow VC to start with unsynced BN

* Set VC to do parallel key loading

* Don't default to dummy eth1 backend

* Add endpoint to dump operation pool

* Add metrics for op pool

* Remove state clone for slot notifier

* Add mem size approximation for tree hash cache

* Avoid cloning tree hash when getting head

* Avoid cloning tree hash when getting head

* Add working arena-based cached tree hash

* Add another benchmark

* Add pre-allocation for caches

* Make cache nullable

* Fix bugs in cache tree hash

* Add validator tree hash optimization

* Optimize hash_concat

* Make hash32_concat return fixed-len array

* Fix failing API tests

* Add new beacon state cache struct

* Add validator-specific cache

* Separate list and values arenas

* Add parallel validator registry hashing

* Remove MultiTreeHashCache

* Remove cached tree hash macro

* Fix failing tree hash test

* Address Michael's comments

* Add CachedTreeHash impl for ef tests

* Fix messy merge conflict

* Optimize attestation production

* Add first basic optimizations

* Fix SlotOutOfBounds error

* Resolved missed merge conflicts

* Fix another missed merge conflict

* Fix more merge conflict issues

* Add `StateSkipConfig`

* Fix test compile errors

* Add failing test

* Fix bug, make tests pass

* Add comment

* Delete unused function

* Replace deleted comment

beacon_node/beacon_chain/src/lib.rs

@@ -17,6 +17,7 @@ mod timeout_rw_lock;
 
 pub use self::beacon_chain::{
     AttestationProcessingOutcome, BeaconChain, BeaconChainTypes, BlockProcessingOutcome,
+    StateSkipConfig,
 };
 pub use self::checkpoint::CheckPoint;
 pub use self::errors::{BeaconChainError, BlockProductionError};