Feat/tooltips

[samialfattani]

This PR adds the feature of enabling the Bootstrap tooltip where it can be inserted within adding a new view like this:

    view = MyModelView(Model1, param, name="Model1", tooltip="tooltip of Model1")
    admin.add_view(view)

Moreover, users can add tooltip anywhere using normal Bootstrap tooltip as follows:

<a title="tooltip message with <b>HTML enabled</b>"
     href="/admin/" 
     data-role="tooltip"
     data-toggle="tooltip" data-placement="bottom" data-html="true"
>
/admin/
</a>

Tests and Docs are updated