Add Async image loading

Examples/Time Travel/SwiftUITimeTravel/TimeTravelView/TimeTravelView.swift

@@ -0,0 +1,39 @@
+import SwiftUI
+
+public struct TimeTravelView<StateType, Content>: View where StateType: StateMachine, Content: View {
+    
+    let initialState: StateType
+    
+    private let content: Content
+    
+    @State var store: Store<StateType>? = nil
+    
+    public init(initialState: StateType, content: () -> Content) {
+        self.initialState = initialState
+        self.content = content()
+    }
+    
+    public var body: some View {
+        
+        let store = self.store ?? Store(state: initialState)
+        if (self.store == nil) {
+            self.store = store
+        }
+
+        return VStack {
+            content
+            TimeTravelBarView()
+        }
+        .environmentObject(store)
+    }
+}
+
+#if DEBUG
+struct TimeTravelView_Previews : PreviewProvider {
+    static var previews: some View {
+        TimeTravelView(initialState: TodoState()) {
+            TodoListView()
+        }
+    }
+}
+#endif