Utils: Add a basic implementation of an EncryptionManager which allows to store the password encrypted.
This use the latest AndroidKeyStore from Android M and allow to store the key securely.
<menu xmlns:android="http://schemas.android.com/apk/res/android">
<item android:id="@+id/privacy_list_context_menu_buddies_item"
android:title="@string/privacy_list_select_dialog_buddies" />
<item android:id="@+id/privacy_list_context_menu_groups_item"
android:title="@string/privacy_list_select_dialog_groups" />
<item android:id="@+id/privacy_list_context_menu_delete_item"
android:title="@string/privacy_list_select_dialog_delete" />
</menu>