Cascades

[RustyDev]

I've noticed a few things about cascading when deleting various models.

If a user likes a post and either the user or the post is deleted, the likes aren't deleted as well and the counts don't update.

[JesusLeon]

It would be definitely nice if this is in the package out-of-the-box. But I think it relies more on the application logic.

@RustyDev you could easily add an observer to update the likes data in that scenario. But of course it would be even better if you could send a PR with such functionality :)

[rtconner]

I haven't had to add a config file to this library yet, but if I add this feature I'll want to put in a config file for it. To make the cascade optional.