Refactor user defined views to regular platform views about spots

[onmyway133]

@zenangst I think the first easy step is for the user to use UIView subclass, and Spots adds that to UITableViewCell and UICollectionViewCell depending on which Spotable it is.

[zenangst]

@onmyway133 yeah I think we can create a TableItemWrapper class that inherits from UITableViewCell, it gets configured with the view that gets resolved from Registry. UICollectionView would have the equivalent, CollectionItemWrapper that inherits from UICollectionViewCell.

One thing that could be "tricky" is how we implement prepareForReuse but that should totally be solvable in a generic and easy way.

It could diff the current view with the one that is already configured and then check if the view is SpotConfigurable.

[zenangst]

I'm gonna start researching this a bit.

[zenangst]

I've created a branch for this, it is sort of a proof on concept but it works really great.
I think this could go into Spots 5.9.0 instead of of being a part of the 6.0.0 milestone.

[zenangst]

This feature is now on master 🚀