add monotonic transition to kovan (#5587) (#5630)

json/src/spec/authority_round.rs

@@ -46,6 +46,9 @@ pub struct AuthorityRoundParams {
 	/// See main AuthorityRoundParams docs.
 	#[serde(rename="eip155Transition")]
 	pub eip155_transition: Option<Uint>,
+	/// Block from which monotonic steps start.
+	#[serde(rename="validateStepTransition")]
+	pub validate_step_transition: Option<Uint>,
 }
 
 /// Authority engine deserialization.
@@ -71,7 +74,8 @@ mod tests {
 				},
 				"blockReward": "0x50",
 				"startStep" : 24,
-				"eip155Transition": "0x42"
+				"eip155Transition": "0x42",
+				"validateStepTransition": 150
 			}
 		}"#;