Reimplement eventWithName method to make changes backwards compatible.

Sources/StateMachine.swift

@@ -252,15 +252,22 @@ open class StateMachine<T:Hashable> {
         }.first
     }
 
-    /// Retrieve event with specific name
+    /// Retrieve events with specific name
     /// - Parameter name: Name of the event
-    /// - Returns: event, if found.
+    /// - Returns: events with specified name, if found.
     open func eventsWithName(_ name: String) -> [Event<T>] {
-        return events.filter { (element) -> Bool in
+        return events.filter { element in
             return element.name == name
         }
     }
 
+    /// Retrieve event with specific name
+    /// - Parameter name: Name of the event
+    /// - Returns: event, if found.
+    open func eventWithName(_ name: String) -> Event<T>? {
+        return eventsWithName(name).first
+    }
+
     /// Check, whether state machine is in concrete state
     /// - Parameter stateValue: value of state to check for
     /// - Returns: whether state machine is in this state.