Minimal switch of substrate-node to GRANDPA /Aura (#1128)

* add beginnings of SRML grandpa library

* get srml-grandpa compiling

* tests for srml-grandpa

* add optional session integration to grandpa SRML

* start integration into node runtime

* Allow extracting pending change from header digest

* Make it compile on wasm

* make tests compile again

* Move Authority Key fetching into service, simplify service factory construction

* Generalize Authority Consensus Setup system

* Add Authority Setup Docs

* Allow CLI params to be extensible

 - move params to structopts
 - split parsing and default command execution
 - add custom config to node
 - extended parsing of custom config
 - extending params via structop's flatten

* Minor fixes on cli extension params:
 - added docs
 - re-add actual app name, rather than node-name
 - make strategy and subcommand optional

* better cli params

* synchronize GRANDPA and normal node authorities

* Implement grandpa::network for gossip consensus

* run_grandpa in Node

* Fix missed merge error

* Integrate grandpa import queue

* more specific type def

* link up linkhalf and import block

* make grandpa future send

* get compiling

* Fix new params convention and license header

* get it running

* rebuild node runtime WASM

* change logging level

* Update node/cli/src/params.rs

Co-Authored-By: rphmeier <rphmeier@gmail.com>

* Update node/cli/src/params.rs

Co-Authored-By: rphmeier <rphmeier@gmail.com>

* Update node/cli/src/lib.rs

Co-Authored-By: rphmeier <rphmeier@gmail.com>

* Update node/runtime/src/lib.rs

Co-Authored-By: rphmeier <rphmeier@gmail.com>

* Update node/cli/src/lib.rs

Co-Authored-By: rphmeier <rphmeier@gmail.com>

* Clean up and Fixme for mutable config

* Move GrandpaService Integration into grandpa, feature gated but on per default

* Fixing grandpa runtime module test

* Update wasm runtime hashes for tests

* GRANDPA: use post-header hash when logging scheduled changes

* add an extra bit of logging to authorities

* fixing missing constrain

* remove old code

* move `NewAuthorities` to an event in srml-grandpa

* fix node-executor tests to use grandpa log

* Remove GossipConsensus from tests, use newly provided sync-feature, fixes tests

* Update to latest wasm runtimes

* address grumbles

* address grumbles

* only derive deserialize when using std

* Clean up use of Deserialize

substrate/core/consensus/common/src/block_import.rs

@@ -1,7 +1,25 @@
+// Copyright 2017-2018 Parity Technologies (UK) Ltd.
+// This file is part of Substrate.
+
+// Substrate is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+
+// Substrate is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with Substrate.  If not, see <http://www.gnu.org/licenses/>.
+
+//! Block import helpers.
 
 use primitives::AuthorityId;
-use runtime_primitives::traits::{Block as BlockT, DigestItemFor};
+use runtime_primitives::traits::{Block as BlockT, Header as HeaderT, DigestItemFor};
 use runtime_primitives::Justification;
+use std::borrow::Cow;
 
 /// Block import result.
 #[derive(Debug)]
@@ -89,6 +107,24 @@ impl<Block: BlockT> ImportBlock<Block> {
 			self.auxiliary,
 		)
 	}
+
+	/// Get a handle to full header (with post-digests applied).
+	pub fn post_header(&self) -> Cow<Block::Header> {
+		use runtime_primitives::traits::Digest;
+
+		if self.post_digests.is_empty() {
+			Cow::Borrowed(&self.header)
+		} else {
+			Cow::Owned({
+				let mut hdr = self.header.clone();
+				for digest_item in &self.post_digests {
+					hdr.digest_mut().push(digest_item.clone());
+				}
+
+				hdr
+			})
+		}
+	}
 }
 
 
@@ -101,4 +137,4 @@ pub trait BlockImport<B: BlockT> {
 		block: ImportBlock<B>,
 		new_authorities: Option<Vec<AuthorityId>>
 	) -> Result<ImportResult, Self::Error>;
-}
+}