Phase 1 of repo reorg (#719)

* Remove unneeded script

* Rename Substrate Demo -> Substrate

* Rename demo -> node

* Build wasm from last rename.

* Merge ed25519 into substrate-primitives

* Minor tweak

* Rename substrate -> core

* Move substrate-runtime-support to core/runtime/support

* Rename/move substrate-runtime-version

* Move codec up a level

* Rename substrate-codec -> parity-codec

* Move environmental up a level

* Move pwasm-* up to top, ready for removal

* Remove requirement of s-r-support from s-r-primitives

* Move core/runtime/primitives into core/runtime-primitives

* Remove s-r-support dep from s-r-version

* Remove dep of s-r-support from bft

* Remove dep of s-r-support from node/consensus

* Sever all other core deps from s-r-support

* Forgot the no_std directive

* Rename non-SRML modules to sr-* to avoid match clashes

* Move runtime/* to srml/*

* Rename substrate-runtime-* -> srml-*

* Move srml to top-level

substrate/core/rpc/src/metadata.rs

@@ -0,0 +1,54 @@
+// 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/>.
+
+//! RPC Metadata
+use std::sync::Arc;
+
+use jsonrpc_pubsub::{Session, PubSubMetadata};
+use rpc::futures::sync::mpsc;
+
+/// RPC Metadata.
+///
+/// Manages persistent session for transports that support it
+/// and may contain some additional info extracted from specific transports
+/// (like remote client IP address, request headers, etc)
+#[derive(Default, Clone)]
+pub struct Metadata {
+	session: Option<Arc<Session>>,
+}
+
+impl ::rpc::Metadata for Metadata {}
+impl PubSubMetadata for Metadata {
+	fn session(&self) -> Option<Arc<Session>> {
+		self.session.clone()
+	}
+}
+
+impl Metadata {
+	/// Create new `Metadata` with session (Pub/Sub) support.
+	pub fn new(transport: mpsc::Sender<String>) -> Self {
+		Metadata {
+			session: Some(Arc::new(Session::new(transport))),
+		}
+	}
+
+	/// Create new `Metadata` for tests.
+	#[cfg(test)]
+	pub fn new_test() -> (mpsc::Receiver<String>, Self) {
+		let (tx, rx) = mpsc::channel(1);
+		(rx, Self::new(tx))
+	}
+}