Deleted abstract Action class and created LoadTimersAction,

TimersLoadedAction, TimersNotLoadedAction, AddTimerAction,
UpdateTimerAction and DeleteTimerAction

Signed-off-by: Andreas Fahrecker <AndreasFahrecker@gmail.com>

lib/actions/timer_actions.dart

@@ -1,9 +1,30 @@
 import 'package:time_progress_calculator/models/timer.dart';
 
-abstract class Action {}
+class LoadTimersAction {}
 
-class UpdateTimerAction extends Action {
+class TimersLoadedAction {
+  final List<Timer> timers;
+
+  TimersLoadedAction(this.timers);
+}
+
+class TimersNotLoadedAction {}
+
+class AddTimerAction {
+  final Timer timer;
+
+  AddTimerAction(this.timer);
+}
+
+class UpdateTimerAction {
+  final String id;
   final Timer updatedTimer;
 
-  UpdateTimerAction(this.updatedTimer);
-}
+  UpdateTimerAction(this.id, this.updatedTimer);
+}
+
+class DeleteTimerAction {
+  final String id;
+
+  DeleteTimerAction(this.id);
+}