The work includes the reactor which ties together all the seperate routines involved in the design of the blockchain v2 refactor. This PR replaces #4067 which got far too large and messy after a failed attempt to rebase.

## Commits:

* Blockchainv 2 reactor:

	+ I cleaner copy of the work done in #4067 which fell too far behind and was a nightmare to rebase.
	+ The work includes the reactor which ties together all the seperate routines involved in the design of the blockchain v2 refactor.

* fixes after merge

* reorder iIO interface methodset

* change iO -> IO

* panic before send nil block

* rename switchToConsensus -> trySwitchToConsensus

* rename tdState -> tmState

* Update blockchain/v2/reactor.go

Co-Authored-By: Bot from GolangCI <42910462+golangcibot@users.noreply.github.com>

* remove peer when it sends a block unsolicited

* check for not ready in markReceived

* fix error

* fix the pcFinished event

* typo fix

* add documentation for processor fields

* simplify time.Since

* try and make the linter happy

* some doc updates

* fix channel diagram

* Update adr-043-blockchain-riri-org.md

* panic on nil switch

* liting fixes

* account for nil block in bBlockResponseMessage

* panic on duplicate block enqueued by processor

* linting

* goimport reactor_test.go

Co-authored-by: Bot from GolangCI <42910462+golangcibot@users.noreply.github.com>
Co-authored-by: Anca Zamfir <ancazamfir@users.noreply.github.com>
Co-authored-by: Marko <marbar3778@yahoo.com>
Co-authored-by: Anton Kaliaev <anton.kalyaev@gmail.com>

* Fix many golint errors

* Fix golint errors in the 'lite' package

* Don't export Pool.store

* Fix typo

* Revert unwanted changes

* Fix errors in counter package

* Fix linter errors in kvstore package

* Fix linter error in example package

* Fix error in tests package

* Fix linter errors in v2 package

* Fix linter errors in consensus package

* Fix linter errors in evidence package

* Fix linter error in fail package

* Fix linter errors in query package

* Fix linter errors in core package

* Fix linter errors in node package

* Fix linter errors in mempool package

* Fix linter error in conn package

* Fix linter errors in pex package

* Rename PEXReactor export to Reactor

* Fix linter errors in trust package

* Fix linter errors in upnp package

* Fix linter errors in p2p package

* Fix linter errors in proxy package

* Fix linter errors in mock_test package

* Fix linter error in client_test package

* Fix linter errors in coretypes package

* Fix linter errors in coregrpc package

* Fix linter errors in rpcserver package

* Fix linter errors in rpctypes package

* Fix linter errors in rpctest package

* Fix linter error in json2wal script

* Fix linter error in wal2json script

* Fix linter errors in kv package

* Fix linter error in state package

* Fix linter error in grpc_client

* Fix linter errors in types package

* Fix linter error in version package

* Fix remaining errors

* Address review comments

* Fix broken tests

* Reconcile package coregrpc

* Fix golangci bot error

* Fix new golint errors

* Fix broken reference

* Enable golint linter

* minor changes to bring golint into line

* fix failing test

* fix pex reactor naming

* address PR comments

+ MockReporeter.Report should return an error to adhere to the
    `behaviour.Reporter` interface

* Move peer behaviour into it's own package
* refactor wip
* Adjust API and fix tests
* remove unused test struct
* Better error message
* Restructure:
    + Now behaviour is it's own package, we don't need to include
    PeerBehaviour in every type.
    + Split up behaviours and reporters into seperate files

* doc string fixes
* Fix minor typos
* Update behaviour/reporter.go
Co-Authored-By: Anton Kaliaev <anton.kalyaev@gmail.com>

* Update behaviour/reporter.go
Co-Authored-By: Anton Kaliaev <anton.kalyaev@gmail.com>