implement data model binding

assets/scripts/navigation.lua

@@ -6,8 +6,11 @@ local screens = {
     home = "screens/home.rml",
     lock = "screens/lock.rml",
     dialer = "screens/dialer.rml",
+    calling = "screens/calling.rml",
     contacts = "screens/contacts.rml",
+    contact_detail = "screens/contact_detail.rml",
     messages = "screens/messages.rml",
+    chat = "screens/chat.rml",
     settings = "screens/settings.rml",
     browser = "screens/browser.rml"
 }