Consensus Engines Implementation: Aura (#911)

* Generalize BlockImport

 - move ImportBlock, BlockOrigin, ImportResult into shared sr-primitives
 - let Consensus provide  and  traits again
 - update consensus traits to latest development
 - implement traits on client::Client, test_client::TestClient
 - update RHD to use the new import_block API

* Move ImportBlock into consensus-common
* Send import notification in aura tests
* Integrating aura into service
* Make Signatures more generic
* Aura Block Production with the given key
* run aura on the thread pool
* start at exact step start in aura
* Add needed wasm blob, in leiu of better solutions.
* Make API ids consistent with traits and bring upstream for sharing.
* Add decrease_free_balance to Balances module
* Encode `Metadata` once instead of two times
* Bitops include xor
* Upgrade key module.
* Default pages to somewhat bigger.
* Introduce upgrade key into node
* Add `Created` event

substrate/core/service/src/chain_ops.rs

@@ -20,11 +20,12 @@ use std::{self, io::{Read, Write}};
 use futures::Future;
 use serde_json;
 
-use client::BlockOrigin;
 use runtime_primitives::generic::{SignedBlock, BlockId};
 use runtime_primitives::traits::{As, Block, Header};
 use network::import_queue::{ImportQueue, BlockData};
 use network::message;
+
+use consensus_common::BlockOrigin;
 use components::{self, Components, ServiceFactory, FactoryFullConfiguration, FactoryBlockNumber, RuntimeGenesis};
 use new_client;
 use codec::{Decode, Encode};