* add context
* extract chain events
* run commit in goroutines
* mine only on canonical
* typo
* linters
* fmt
* mark unused methods
* restore stress test
* test single miner
* remove unsafe Trie storage
* remove locks from miner
* restore interrupt
* remove result goroutine
* remove unconfirmedBlocks
* cherry-pick 04a1d475ff1a36ad8f92fec80385df18c52bdc1f
* extract uncles
* one miner succeeded
* restore context cancel
* cleanup
* skip an unstable test
* remove pending state
* use context instead of interrupt func
* calculate sealHash only once
* comment out unstable test
* after merge
* fix after merge
Co-authored-by: ledgerwatch <akhounov@gmail.com>
