Replace ethcore-logger with env-logger. (#10102)

* Replace ethcore-logger with env-logger.

* Fix logger initialization in WASM tests.

* uncomment logger initialization in secret store

* Don't use ethcore-logger in whisper.

* Move ethcore-logger within parity dir.

* Uncomment rest from secret-store.

* Use `let _ =` in private_contract for consistency

* `ok()` to `let _ =` fix in service

* Use `let _ = ` for state_db

rpc/src/v1/impls/parity.rs

@@ -167,6 +167,7 @@ impl<C, M, U, S> Parity for ParityClient<C, M, U> where
 	}
 
 	fn dev_logs(&self) -> Result<Vec<String>> {
+		warn!("This method is deprecated and will be removed in future. See PR #10102");
 		let logs = self.logger.logs();
 		Ok(logs.as_slice().to_owned())
 	}