Add Telegram extension example

[ricardopereira]

Remote log using a Telegram group.

[ricardopereira]

@objc class CriticalLogger: NSObject {

    private struct Payload: Codable {
        let chat: String
        let text: String

        private enum CodingKeys : String, CodingKey {
            case chat = "chat_id", text
        }
    }

    private static let token = <telegram_token>

    @objc class func remoteLog(_ text: String) {
        #if !DEBUG
        let payload = Payload(
            chat: "-484357798",
            text: text + " (v" + Bundle.main.appVersionDescription + ")"
        )

        let components = URLComponents(string: "https://api.telegram.org")
        guard let url = components?.url?.appendingPathComponent("bot\(token)").appendingPathComponent("sendMessage") else {
            print("No URL"); return
        }

        var request = URLRequest(url: url)
        do {
            request.httpBody = try JSONEncoder().encode(payload)
        }
        catch {
            print(error.localizedDescription)
        }
        request.httpMethod = "POST"
        request.addValue("application/json", forHTTPHeaderField: "Content-Type")

        let task = URLSession.shared.dataTask(with: request) { data, response, error in
            if let data = data, let str = String(data: data, encoding: .utf8) {
                logEntry("Critical Logger data: \(str)", level: .verbose)
            }
            if let response = response {
                logEntry("Critical Logger response: \(response)", level: .verbose)
            }
            if let error = error {
                logError(error, title: "Critical Logger")
            }
        }
        task.resume()
        #endif
    }

}