* Validator improvements
* Fix cancelling state serialization
* Disable state serializer on all mainnet validators
* Flag --catchain-max-block-delay-slow
* Set default catchain-max-block-delay to 0.4, delay-slow to 1.0
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Co-authored-by: SpyCheese <mikle98@yandex.ru>
* Fix double serialization of masterchain; increase sync_blocks_before
* Improve logging in DownloadState
* Write persistent state directly to file instead of a buffer
* Don't keep ref to masterchain state in AsyncStateSerializer
* Sparse state serialization over longer period
Co-authored-by: SpyCheese <mikle98@yandex.ru>