add device model

src/tamagotchi-service/src/main/java/com/sap/tamagotchi/model/Color.java

@@ -0,0 +1,5 @@
+package com.sap.tamagotchi.model;
+
+public enum Color {
+    RED, YELLOW, BLUE, GREEN
+}

src/tamagotchi-service/src/main/java/com/sap/tamagotchi/model/Device.java

@@ -1,4 +1,46 @@
 package com.sap.tamagotchi.model;
 
-public class Device {
+import java.time.Instant;
+import java.util.Collection;
+import java.util.Collections;
+import java.util.Queue;
+import java.util.UUID;
+import java.util.concurrent.ConcurrentLinkedQueue;
+
+public class Device extends Thread {
+
+    private final String getDeviceId = UUID.randomUUID().toString();
+    private final String owner;
+    private final Color color;
+    private final Instant born = Instant.now();
+    private final Queue<String> messages = new ConcurrentLinkedQueue<String>();
+
+    public Device(String owner, Color color) {
+        this.owner = owner;
+        this.color = color;
+    }
+
+    public String getDeviceId() {
+        return getDeviceId;
+    }
+
+    public String getOwner() {
+        return owner;
+    }
+
+    public Color getColor() {
+        return color;
+    }
+
+    public Instant getBorn() {
+        return born;
+    }
+
+    public boolean hasMessages() {
+        return !messages.isEmpty();
+    }
+
+    public Collection<IoTMessage> getMessages() {
+        return Collections.emptyList();
+    }
 }