ReusableCell for easy dequeueing in UITableView.

ReusableCell.swift

/// ReusableCell for easy dequeueing in table views. Use UITableView.dequeueReusableCell().
protocol ReusableCell {
  static var reuseIdentifier: String { get }
  init()
}

extension UITableView {
  /// Dequeues a ReusableCell or allocates a new ReusableCell.
  func dequeueReusableCell<Cell: ReusableCell>() -> Cell {
    return dequeueReusableCell(withIdentifier: Cell.reuseIdentifier) as? Cell ?? Cell()
  }
}