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/node/runtime/wasm/Cargo.lock

@@ -285,6 +285,7 @@ dependencies = [
  "srml-system 0.1.0",
  "srml-timestamp 0.1.0",
  "srml-treasury 0.1.0",
+ "srml-upgrade-key 0.1.0",
  "substrate-primitives 0.1.0",
 ]
 
@@ -817,6 +818,24 @@ dependencies = [
  "substrate-primitives 0.1.0",
 ]
 
+[[package]]
+name = "srml-upgrade-key"
+version = "0.1.0"
+dependencies = [
+ "hex-literal 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "parity-codec 2.1.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "parity-codec-derive 2.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "serde 1.0.79 (registry+https://github.com/rust-lang/crates.io-index)",
+ "serde_derive 1.0.79 (registry+https://github.com/rust-lang/crates.io-index)",
+ "sr-io 0.1.0",
+ "sr-primitives 0.1.0",
+ "sr-std 0.1.0",
+ "srml-consensus 0.1.0",
+ "srml-support 0.1.0",
+ "srml-system 0.1.0",
+ "substrate-primitives 0.1.0",
+]
+
 [[package]]
 name = "stable_deref_trait"
 version = "1.1.1"