Rewrite of Remote Smart Card Reader

- use material design
- use AsyncTask instead of Runnable for VPCDWorker to integrate with the
  App's lifecycle
- use a dedicated Preference Activity
- integrated zxing's QR code scanner
- use Snackbar instead of Toast
- capture debug messages in log instead of explicitly passing messages
- use reader mode only, breaks support of Android before kitkat

remote-reader/remote-reader.iml

@@ -13,7 +13,7 @@
     <content url="file://$MODULE_DIR$">
       <excludeFolder url="file://$MODULE_DIR$/.gradle" />
     </content>
-    <orderEntry type="jdk" jdkName="1.7" jdkType="JavaSDK" />
+    <orderEntry type="inheritedJdk" />
     <orderEntry type="sourceFolder" forTests="false" />
   </component>
 </module>