Deduplicate registrar contract & calling logic (#11110)

* Rename RegistryInfo -> RegistryInfoDeprecated

* Add BlockId parameter to Registrar::get_address and RegistrarClient::call_contract

* Remove RegistrarClient::Call (use async for now); add RegistrarClient::get_address

* Remove Registrar type in favour of naked trait

* Use CallContract trait bound instead of separate call_contract method

* Make RegistrarClient::get_address and URLHint::resolve synchronous

* RegistrarClient::get_address: return check if address is zero

* Modify RegistryInfo::registry_address to take &str

* return Result from RegistryInfo::registry_address

* Replace RegistryInfo with RegistrarClient

- Modifed RegistrarClient::registrar_address to return Option
- Removed BlockChainClient::registrar_address

* Fix other build configs

* Fix unit test builds

* Remove local RegistrarClient type from run::execute_impl

* Remove registrar.json from ethcore

* Formatting/line breaks

* Update RegistrarClient docs, remove explicit lifetime

* Weak ref to ethcore client from hash fetch client

* Fix unit tests

ethcore/src/miner/mod.rs

@@ -46,7 +46,8 @@ use types::{
 };
 
 use block::SealedBlock;
-use call_contract::{CallContract, RegistryInfo};
+use call_contract::CallContract;
+use registrar::RegistrarClient;
 use client::{BlockProducer, SealedBlockImporter};
 use client_traits::{BlockChain, ChainInfo, AccountData, Nonce, ScheduleInfo};
 use account_state::state::StateInfo;
@@ -54,7 +55,7 @@ use account_state::state::StateInfo;
 /// Provides methods to verify incoming external transactions
 pub trait TransactionVerifierClient: Send + Sync
 	// Required for ServiceTransactionChecker
-	+ CallContract + RegistryInfo
+	+ CallContract + RegistrarClient
 	// Required for verifiying transactions
 	+ BlockChain + ScheduleInfo + AccountData
 {}