infinity-loader needs to unhide on model change

The infinity-loader will stop functioning permanently on infinity when hideOnInfinity=true. However, when the model changes and has new content because of a change in filters (similar to #331), the infinity-loader should unhide itself because we’ve no longer reached infinity.

I think a property on the model should be watched inside the infinity-loader helper. Not sure what that property should be, but probably something like isLoaded, isDoneLoading, canLoadMore or something that resets when the model changes.

[snewcomer]

Thank you for the issue! What we ultimately need to do is observe reachedInfinity and reset isVisible when it changes to false. #413

One day, we can move away from observers, but for now I think the referenced PR fixes it.

[Redsandro]

Does this mean we can use the one-liner again without wrapping it in {{#unless model.reachedInfinity}}? That would be great!