Add forwarding for /v2/

src/main/java/de/thm/arsnova/controller/v2/WelcomeController.java

+package de.thm.arsnova.controller.v2;
+
+import org.springframework.stereotype.Controller;
+import org.springframework.web.bind.annotation.RequestMapping;
+
+@Controller("v2WelcomeController")
+@RequestMapping("/v2")
+public class WelcomeController {
+	@RequestMapping(value = "/")
+	public String forwardHome() {
+		return "forward:/";
+	}
+}