Extract snapshot to own crate (#11010)

* Move snapshot to own crate
Sort out imports

* WIP cargo toml

* Make snapshotting generic over the client
Sort out tests

* Sort out types from blockchain and client

* Sort out sync

* Sort out imports and generics

* Sort out main binary

* Fix sync test-helpers

* Sort out import for secret-store

* Sort out more imports

* Fix easy todos

* cleanup

* Cleanup

* remove unneded workspace member

* cleanup

* Sort out test-helpers dependency on account-db

* Update ethcore/client-traits/src/lib.rs

Co-Authored-By: Niklas Adolfsson <niklasadolfsson1@gmail.com>

* Update ethcore/snapshot/Cargo.toml

ethcore/sync/src/tests/helpers.rs

@@ -22,11 +22,17 @@ use bytes::Bytes;
 use network::{self, PeerId, ProtocolId, PacketId, SessionInfo};
 use network::client_version::ClientVersion;
 use tests::snapshot::*;
-use types::io_message::ClientIoMessage;
-use client_traits::BlockChainClient;
-use ethcore::client::{TestBlockChainClient, Client as EthcoreClient,
-	ClientConfig, ChainNotify, NewBlocks, ChainMessageType};
-use ethcore::snapshot::SnapshotService;
+use types::{
+	chain_notify::{NewBlocks, ChainMessageType},
+	io_message::ClientIoMessage,
+};
+use client_traits::{BlockChainClient, ChainNotify};
+use ethcore::client::{
+	TestBlockChainClient,
+	Client as EthcoreClient,
+	ClientConfig,
+};
+use snapshot::SnapshotService;
 use spec::{self, Spec};
 use ethcore_private_tx::PrivateStateDB;
 use ethcore::miner::Miner;

ethcore/sync/src/tests/snapshot.rs

@@ -20,7 +20,7 @@ use hash::keccak;
 use ethereum_types::H256;
 use parking_lot::Mutex;
 use bytes::Bytes;
-use ethcore::snapshot::SnapshotService;
+use snapshot::SnapshotService;
 use ethcore::client::EachBlockWith;
 use types::{
 	BlockNumber,