Make tableviews a bit safer

TableViewCellType.swift

protocol CellType {
  static var identifier: String { get }
}

extension CellType {
  static var identifier: String { return "\(Self.self)" }
}

extension UITableView {
  func register<Cell>(forReuse cell: Cell.Type)
    where Cell: CellType, Cell: UITableViewCell
  {
    register(Cell.self, forCellReuseIdentifier: Cell.identifier)
  }
  
  func dequeueReusable<Cell>(_ cellType: Cell.Type, for indexPath: IndexPath) -> Cell?
    where Cell: CellType, Cell: UITableViewCell
  {
    return dequeueReusableCell(withIdentifier: Cell.identifier, for: indexPath) as? Cell
  }
}

extension StoryCell: CellType {}