[stzn/the-swift-programming-language-jp] Issue opened: #670 trailing commaの例を追加

[stzn/the-swift-programming-language-jp] Issue opened: #671 文言の明確化

[stzn/the-swift-programming-language-jp] Issue opened: #672 ~Pシンタックス追加

[stzn/the-swift-programming-language-jp] Issue opened: #673 文法のサマリーページ生成(自動化)