Reorganising the repository - external renames and moves (#4074)

* Adding first rough ouline of the repository structure

* Remove old CI stuff

* add title

* formatting fixes

* move node-exits job's script to scripts dir

* Move docs into subdir

* move to bin

* move maintainence scripts, configs and helpers into its own dir

* add .local to ignore

* move core->client

* start up 'test' area

* move test client

* move test runtime

* make test move compile

* Add dependencies rule enforcement.

* Fix indexing.

* Update docs to reflect latest changes

* Moving /srml->/paint

* update docs

* move client/sr-* -> primitives/

* clean old readme

* remove old broken code in rhd

* update lock

* Step 1.

* starting to untangle client

* Fix after merge.

* start splitting out client interfaces

* move children and blockchain interfaces

* Move trie and state-machine to primitives.

* Fix WASM builds.

* fixing broken imports

* more interface moves

* move backend and light to interfaces

* move CallExecutor

* move cli off client

* moving around more interfaces

* re-add consensus crates into the mix

* fix subkey path

* relieve client from executor

* starting to pull out client from grandpa

* move is_decendent_of out of client

* grandpa still depends on client directly

* lemme tests pass

* rename srml->paint

* Make it compile.

* rename interfaces->client-api

* Move keyring to primitives.

* fixup libp2p dep

* fix broken use

* allow dependency enforcement to fail

* move fork-tree

* Moving wasm-builder

* make env

* move build-script-utils

* fixup broken crate depdencies and names

* fix imports for authority discovery

* fix typo

* update cargo.lock

* fixing imports

* Fix paths and add missing crates

* re-add missing crates

substrate/primitives/trie/src/error.rs

@@ -0,0 +1,47 @@
+// Copyright 2015-2017 Parity Technologies
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+#[cfg(feature="std")]
+use std::fmt;
+#[cfg(feature="std")]
+use std::error::Error as StdError;
+
+#[derive(Debug, PartialEq, Eq, Clone)]
+/// Error for trie node decoding.
+pub enum Error {
+	/// Bad format.
+	BadFormat,
+	/// Decoding error.
+	Decode(codec::Error)
+}
+
+impl From<codec::Error> for Error {
+	fn from(x: codec::Error) -> Self {
+		Error::Decode(x)
+	}
+}
+
+#[cfg(feature="std")]
+impl StdError for Error {
+	fn description(&self) -> &str {
+		match self {
+			Error::BadFormat => "Bad format error",
+			Error::Decode(_) => "Decoding error",
+		}
+	}
+}
+
+#[cfg(feature="std")]
+impl fmt::Display for Error {
+	fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+		match self {
+			Error::Decode(e) => write!(f, "Decode error: {}", e.what()),
+			Error::BadFormat => write!(f, "Bad format"),
+		}
+	}
+}