Expunge error-chain (feat. tomaka) (#2662)

* Remove error_chain

* Expunge error-chain from rpc and service.

* Expunge from transaction pool.

* Expunge from node/cli

* Expunge from keystore.

* Remove some boilerplate.

* Fix remaining stuff.

* Improve on deprecation message.

* Fix issues.

* Fix trnsaction pool tests.

* Fix the rest.

* Fix borked merge.

* Update lock

substrate/core/service/src/lib.rs

@@ -44,7 +44,7 @@ use runtime_primitives::traits::{Header, SaturatedConversion};
 use substrate_executor::NativeExecutor;
 use tel::{telemetry, SUBSTRATE_INFO};
 
-pub use self::error::{ErrorKind, Error};
+pub use self::error::Error;
 pub use config::{Configuration, Roles, PruningMode};
 pub use chain_spec::{ChainSpec, Properties};
 pub use transaction_pool::txpool::{
@@ -515,7 +515,7 @@ impl<C: Components> network::TransactionPool<ComponentExHash<C>, ComponentBlock<
 			match self.pool.submit_one(&best_block_id, uxt) {
 				Ok(hash) => Some(hash),
 				Err(e) => match e.into_pool_error() {
-					Ok(txpool::error::Error(txpool::error::ErrorKind::AlreadyImported(hash), _)) => {
+					Ok(txpool::error::Error::AlreadyImported(hash)) => {
 						hash.downcast::<ComponentExHash<C>>().ok()
 							.map(|x| x.as_ref().clone())
 					},