lint: Enable Golint ( #4212 )
* 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