Fix bug when creating contact.
The contact is created asynchronously so we cannot try to get it immediatly.
As a consequence the method IRoster.createContact now return a boolean.
<menu xmlns:android="http://schemas.android.com/apk/res/android">
<item android:id="@+id/privacy_list_menu_create" android:visible="true"
android:title="@string/privacy_list_menu_create" android:icon="@android:drawable/ic_menu_add" />
</menu>