move additional_info to engines, fixes registry on non-ethash chains

ethcore/src/machine.rs

@@ -16,7 +16,7 @@
 
 //! Ethereum-like state machine definition.
 
-use std::collections::BTreeMap;
+use std::collections::{BTreeMap, HashMap};
 use std::cmp;
 use std::sync::Arc;
 
@@ -378,6 +378,13 @@ impl EthereumMachine {
 	pub fn supports_wasm(&self) -> bool {
 		self.params().wasm
 	}
+
+	/// Additional params.
+	pub fn additional_params(&self) -> HashMap<String, String> {
+		hash_map![
+			"registrar".to_owned() => self.params.registrar.hex()
+		]
+	}
 }
 
 /// Auxiliary data fetcher for an Ethereum machine. In Ethereum-like machines