Add initial device status service

DeviceStatus/Service/DeviceRepository.cs

@@ -0,0 +1,18 @@
+namespace Service;
+
+public class DeviceRepository : Dictionary<string, Device>
+{
+    public void HandleDeviceMessage(string name, string value)
+    {
+        if (ContainsKey(name))
+        {
+            this[name].Update(value);
+        }
+        else
+        {
+            var device = new Device(name, value);
+
+            this[name] = device;
+        }
+    }
+}