add divider

OpenKeychain/src/main/res/layout/add_keys_activity.xml

@@ -153,6 +153,12 @@
             android:drawablePadding="8dp"
             android:gravity="center_vertical" />
 
+        <View
+            android:layout_width="match_parent"
+            android:layout_height="1dip"
+            android:background="?android:attr/listDivider"
+            android:layout_marginBottom="8dp" />
+
     </LinearLayout>
 
 </LinearLayout>