Instantiating prototype cells

One testing challenge that I have been seeing multiple people run into is that of how to test instances of UITableViewCell/UICollectionViewCell subclasses that are defined as prototype cells in a storyboard. This is difficult because these prototype cells can only be accessed by dequeueing from from the table/collection view in which they are defined, and only during the standard cell loading process of the table/collection view.

I have added a mechanism that turns this process into a one-step method call which instantiates the view controller from a storyboard, configures the table/collection view with a special-purpose data source which is designed to dequeue a cell with a given identifier and expose it for later use.