* 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>
* Improve validator session stats
* Collator stats: block limits, number of processed external messages
* Collator and validator work time
* Last key block seqno
* Approvers and signers
* End validator session stats
- added some fift scripts for the config change proposal voting
- added validator-engine-console support for the config change proposal voting
- additional sanity checks in catchain
- unsafe slow catchain resync method