Initializing `Renderer` without passing the target instance.

[Ryo Aoyama]

Checklist

• Reviewed the README and documents.
• Searched existing issues for ensure not duplicated.

Description

Allow Renderer to be initialized without passing the target instance.

Motivation and Context

Become no need to add lazy to renderer property declarations.
Also, the timing when delegate and dataSource are set in tableView becomes explicit.
Depending on when delegate and dataSource are set, cases have been found where unnecessary space is available above or below the tableView.

Proposed Solution

@IBOutlet weak var tableView: UITableView!

let renderer = Renderer(
    adapter: UITableViewAdapter(),
    updater: UITableViewUpdater()
)

func viewDidLoad() {
    super.viewDidLoad()
    renderer.target = tableView
}