For some dialogs, the models are not loaded when we play the first animations of the dialog. This is because the OnAnimFinished script is executed instantly when the model is not here to play the animations (so the animations are played but instantly).

To fix this, I should change how we handle the OnModelLoaded event (we have one callback for now) to instead use promises (from Ellyb) to make sure any code in the add-on that needs the model to be loaded can use the promise to execute the code then.

Note: Promises are not in the master branch of Ellyb yet, so I will need to finalize those before doing this ticket.