Show only the email clients in Feedback Feature (commons-app#1203)

Instead of showing only the email clients, The Feedback feature was showing multiple unsupported clients (WhatsApp, Bluetooth etc)

* Changes made to let the user choose from the available email related clients only.

Author: ayushin78

app/src/main/java/fr/free/nrw/commons/theme/NavigationBaseActivity.java

@@ -5,6 +5,7 @@
 import android.content.ActivityNotFoundException;
 import android.content.Context;
 import android.content.Intent;
+import android.net.Uri;
 import android.support.annotation.NonNull;
 import android.support.design.widget.NavigationView;
 import android.support.v4.widget.DrawerLayout;
@@ -119,8 +120,9 @@ public boolean onNavigationItemSelected(@NonNull final MenuItem item) {
                 return true;
             case R.id.action_feedback:
                 drawerLayout.closeDrawer(navigationView);
-                Intent feedbackIntent = new Intent(Intent.ACTION_SEND);
+                Intent feedbackIntent = new Intent(Intent.ACTION_SENDTO);
                 feedbackIntent.setType("message/rfc822");
+                feedbackIntent.setData(Uri.parse("mailto:"));
                 feedbackIntent.putExtra(Intent.EXTRA_EMAIL,
                         new String[]{CommonsApplication.FEEDBACK_EMAIL});
                 feedbackIntent.putExtra(Intent.EXTRA_SUBJECT,