* consensus/ethash, params: implement eip-2384: bump difficulty bomb

* params: EIP 2384 compat checks

* consensus, params: add Muir Glacier block number (mainnet,ropsten) + official name

* core/forkid: forkid tests for muir glacier

* params/config: address review concerns

* params, core/forkid: review nitpicks

* cmd/geth,eth,les: add override option for muir glacier

* params: nit fix

params: update CHTs for v1.9.9 release

trie: track dirty cache metrics, track clean writes on commit

This change:

- removes the PostChainEvents method on core.BlockChain.
- sorts 'removed log' events by block number.
- fire the NewChainHead event if we inject a canonical block into the chain
  even if the entire insertion is not successful.
- guarantees correct event ordering in all cases.

The original idea behind this change was to remove a use of the
deprecated CancelRequest method. Simply removing it would've been an
option, but I couldn't resist and did a bit of a refactoring instead.

All remote sealing code was contained in a single giant function. Remote
sealing is now extracted into its own object, remoteSealer.

deps: update fastcache to 1.5.3

core/rawdb: fix reinit regression caused by the hash check PR

* core: fix staticcheck warnings

* fix goimports

* p2p/discover: slow down lookups on empty table

* p2p/discover: wake from slowdown sleep when table is closed

* accounts/keystore: fix staticcheck warnings

* review feedback

* rlp: fix staticcheck warnings

* rlp: fix ExampleDecode test

cmd/geth: remove network id from version cmd

It was reflective only of the Default setting,
and not chain aware.

Numbers were already allowed when creating labels, just not when
referencing them.

* p2p/discv5: add deprecation warning and remove unused code

* p2p/discv5: remove unused variables