Mark the Tag app as requiring the NFC hardware feature.

Change-Id: Idedb6059be0bbda820d3ea50e3434541d1ab085e
diff --git a/AndroidManifest.xml b/AndroidManifest.xml
index 6bebe3e..91b0365 100644
--- a/AndroidManifest.xml
+++ b/AndroidManifest.xml
@@ -26,6 +26,8 @@
     <uses-permission android:name="android.permission.CALL_PHONE" />
     <uses-permission android:name="android.permission.NFC" />
 
+    <uses-feature android:name="android.hardware.nfc" required="true" />
+
     <application
         android:icon="@drawable/ic_launcher_nfc"
         android:label="@string/app_name"