Silence known deprecation warnings (#2651)

* Silence known deprecation warnings

1. Prefixes known instances of usages of client.backend and client.import_lock with `#[allow(deprecated)]` to silence the warnings. 2. Remove file-global `#![allow(deprecated)]` used in these cases. Both to prevent us overlooking externally caused deprecation messages.

* fixing missing ;

* fix missing test cases

* move deprecated markers to make CI happy

* move deprecated markers to make CI happy

* attempt to fix the test

* bumping impl_version of node runtime

* Minor cleanup

substrate/core/network/src/chain.rs

@@ -134,6 +134,7 @@ impl<B, E, Block, RA> Client<Block> for SubstrateClient<B, E, Block, RA> where
 		}
 
 		let tree_route = ::client::blockchain::tree_route(
+			#[allow(deprecated)]
 			self.backend().blockchain(),
 			BlockId::Hash(*block),
 			BlockId::Hash(*base),

substrate/core/network/src/test/mod.rs

@@ -143,6 +143,7 @@ impl PeersClient {
 	}
 
 	pub fn as_in_memory_backend(&self) -> InMemoryBackend<Block, Blake2Hasher> {
+		#[allow(deprecated)]
 		match *self {
 			PeersClient::Full(ref client) => client.backend().as_in_memory(),
 			PeersClient::Light(_) => unimplemented!("TODO"),
@@ -150,6 +151,7 @@ impl PeersClient {
 	}
 
 	pub fn get_aux(&self, key: &[u8]) -> ClientResult<Option<Vec<u8>>> {
+		#[allow(deprecated)]
 		match *self {
 			PeersClient::Full(ref client) => client.backend().get_aux(key),
 			PeersClient::Light(ref client) => client.backend().get_aux(key),