* Groundwork for entry tree, align constants with definitions in the book
* Fix edge case in test, node can keep generating ticks between handle_role_transition and exit() call
* Use vote signer service in fullnode
* Use native types for signature and pubkey, and address other review comments
* Start local vote signer if a remote service address is not provided
* Rebased to master
* Fixes after rebase
* Break out last_ids into its own module
* Boot SignatureNotFound from BankError
* No longer return BankError from LastIds methods
* No longer piggypack on BankError for a LastIds signature status
* Drop all dependencies on the bank
* SignatureStatus -> Status and LastIds -> StatusDeque
* Unstable tests, issue 2193
* Insert blobs into db_ledger in broadcast stage to support leader to validator transitions
* Add transmitting real slots to broadcast stage
* Handle real slots instead of default slots in window
* Switch to dummy repair on slots and modify erasure to support leader rotation
* Shorten length of holding locks
* Remove logger from replicator test
add linked-list capability to accounts
change accounts from a linked list to a VecDeque
add checkpoint and rollback for lastids
add subscriber notifications for rollbacks
checkpoint transaction count, too
* Move finality computation into a service run from the banking stage, ComputeLeaderFinalityService
* Change last ids nth to tick height, remove separate tick height from bank
* Add first leader to genesis entries, consume in genesis.sh
* Set bootstrap leader in the bank on startup, remove instantiation of bootstrap leader from bin/fullnode
* Remove need to initialize bootstrap leader in leader_scheduler, now can be read from genesis entries
* Add separate interface new_with_leader() in mint for creating genesis leader entries
* Add Vote Contract
* Move ownership of LeaderScheduler from Fullnode to the bank
* Modified ReplicateStage to consume leader information from bank
* Restart RPC Services in Leader To Validator Transition
* Make VoteContract Context Free
* Remove voting from ClusterInfo and Tpu
* Remove dependency on ActiveValidators in LeaderScheduler
* Switch VoteContract to have two steps 1) Register 2) Vote. Change thin client to create + register a voting account on fullnode startup
* Remove check in leader_to_validator transition for unique references to bank, b/c jsonrpc service and rpcpubsub hold references through jsonhttpserver
* Add PoH height to process_ledger()
* Moved broadcast_stage Leader Scheduling logic to use Poh height instead of entry_height
* Moved LeaderScheduler logic to PoH in ReplicateStage
* Fix Leader scheduling tests to use PoH instead of entry height
* Change is_leader detection in repair() to use PoH instead of entry height
* Add tests to LeaderScheduler for new functionality
* fix Entry::new and genesis block PoH counts
* Moved LeaderScheduler to PoH ticks
* Cleanup to resolve PR comments