BAEL-1533 Making a Spring MVC Form Remember Values

- add example code
- update pom dependency to spring boot starter 2.0.0.RC2
- update import in SpringApplicationException

spring-5/src/main/java/com/baeldung/sessionattrs/TodoControllerWithScopedProxy.java

@@ -0,0 +1,45 @@
+package com.baeldung.sessionattrs;
+
+import java.time.LocalDateTime;
+
+import org.springframework.stereotype.Controller;
+import org.springframework.ui.Model;
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.ModelAttribute;
+import org.springframework.web.bind.annotation.PostMapping;
+import org.springframework.web.bind.annotation.RequestMapping;
+
+@Controller
+@RequestMapping("/scopedproxy")
+public class TodoControllerWithScopedProxy {
+
+    private TodoList todos;
+
+    public TodoControllerWithScopedProxy(TodoList todos) {
+        this.todos = todos;
+    }
+
+    @GetMapping("/form")
+    public String showForm(Model model) {
+        if (!todos.isEmpty()) {
+            model.addAttribute("todo", todos.peekLast());
+        } else {
+            model.addAttribute("todo", new TodoItem());
+        }
+
+        return "scopedproxyform";
+    }
+
+    @PostMapping("/form")
+    public String create(@ModelAttribute TodoItem todo) {
+        todo.setCreateDate(LocalDateTime.now());
+        todos.add(todo);
+        return "redirect:/scopedproxy/todos.html";
+    }
+
+    @GetMapping("/todos.html")
+    public String list(Model model) {
+        model.addAttribute("todos", todos);
+        return "scopedproxytodos";
+    }
+}