* Update to geth v1.8.14
* Remove patches that were merged upstream
* Apply patches before 0016
* Fix 0016 and apply it
* Apply everything else
* Pass gas limit as a second argument to simulated backend
* add verifier and test using simulated backend
* add ContractCaller
* commit simulated backend after deploy and after smart contract writes
* use bind.NewKeyedTransactor for all transactions in tests
* rename RegistryVerifier to Verifier
* initialize contract verifier if MailServerRegistryAddress config is set
* use contractAddress.Hash()
* refactoring
* use fmt.Sprintf to format contract address in logs
* fix test and lint warnings
* update Gopkg.lock
* update Gopkg.lock once more
Dmitry Shulyak
Andrea Franz