Convert raw collection array into Collections

The default error that happens here is super strange and scary to new people.

My rational is that if someone is passing in a raw array under the collection key we can assume they want a collection. Thus why not take care of this work for them.

This will help to clean up many peoples code and remove an unneeded ivar when you just need a "dumb" collection.

:tada: 

thanks for the idea @jenius
Even though no one should really be keeping a reference to `options` up above, I think we should clone it to prevent modifying the original here.