Force recreation of all pages when calling reloadData

This PR fixes an issue where the pages arn't recreated when calling `reloadData`. For my usage, I need to resetup the pages when a property on the parent container VC changed; this ensures that the delegate method to create each page is called against from scratch. I also think this better reflects the `reloadData` concept from `UITableView`.

Thanks for a great page controller Levi!