Swift support for NetworkPlugin (#201)

Summary:
Solves #173

- [x] Add plugins in the sonarkit xcodeproj so that its easy to debug
- [x] Get rid off the c++ in the headers
- [x] Add example to hit network requests and validate

Have a look at the screen shot below ✨⭐️⚡️

<img width="1677" alt="screen shot 2018-08-02 at 12 46 07 pm" src="https://user-images.githubusercontent.com/3865908/43581809-22efe4fe-9652-11e8-9424-f279d07c5c81.png">
Pull Request resolved: https://github.com/facebook/flipper/pull/201

Reviewed By: danielbuechele

Differential Revision: D9132157

Pulled By: priteshrnandgaonkar

fbshipit-source-id: 2b425506961f02eb2bf629c2bcab0da6e7ce5bb0

iOS/SampleSwift/SampleSwift/NetworkViewController.swift

@@ -0,0 +1,88 @@
+// Copyright 2004-present Facebook. All Rights Reserved.
+
+import UIKit
+
+class NetworkViewController: UIViewController {
+
+  @IBAction func tappedGetAPI(_ sender: UIButton) {
+    let getURL = URL(string: "https://demo9512366.mockable.io/FlipperGet")!
+    let dataTask = URLSession.shared.dataTask(with: getURL){ [weak self] (data, response, error) in
+      guard let strongSelf = self else { return }
+      guard let dataUnwrapped = data else {
+        strongSelf.showAlert(message: "Received no data in GET API")
+        return
+      }
+
+      if let errorUnwrapped = error {
+        strongSelf.showAlert(message: "Received error in GET API Error:\(errorUnwrapped.localizedDescription)")
+        return
+      }
+
+      let dict = try! JSONSerialization.jsonObject(with: dataUnwrapped, options: JSONSerialization.ReadingOptions.init(rawValue: 0)) as! [String: String]
+      // As sonar cannot detect print() in Logs
+      NSLog("MSG-GET: \(dict["msg"] ?? "Did not find msg key in the received response")")
+      strongSelf.showAlert(message: "Received response from GET API, please check the sonar network plugin for detailed response")
+    }
+    dataTask.resume()
+  }
+
+  @IBAction func tappedPOSTAPI(_ sender: UIButton) {
+    guard let postURL = URL(string: "https://demo9512366.mockable.io/FlipperPost") else {
+      showAlert(message: "Check the POST URL")
+      return
+    }
+    var postRequest = URLRequest(url: postURL)
+    postRequest.addValue("application/json", forHTTPHeaderField: "Content-Type")
+    postRequest.addValue("application/json", forHTTPHeaderField: "Accept")
+
+    let dict = ["app" : "Flipper", "remarks": "Its Awesome"]
+    postRequest.httpBody = try! JSONSerialization.data(withJSONObject: dict, options: JSONSerialization.WritingOptions.init(rawValue: 0))
+    postRequest.httpMethod = "POST"
+    let dataTask = URLSession.shared.dataTask(with: postRequest){ [weak self] (data, response, error) in
+      guard let strongSelf = self else { return }
+      guard let dataUnwrapped = data else {
+        strongSelf.showAlert(message: "Received no data in POST API")
+        return
+      }
+
+      if let errorUnwrapped = error {
+        strongSelf.showAlert(message: "Received error in POST API Error:\(errorUnwrapped.localizedDescription)")
+        return
+      }
+
+      let dict = try! JSONSerialization.jsonObject(with: dataUnwrapped, options: JSONSerialization.ReadingOptions.init(rawValue: 0)) as! [String: String]
+      // As sonar cannot detect print() in Logs
+      NSLog("MSG-POST: \(dict["msg"] ?? "Did not find msg key in the received response")")
+      strongSelf.showAlert(message: "Received response from POST API, please check the sonar network plugin for detailed response")
+    }
+    dataTask.resume()
+  }
+
+  @IBAction func tappedFetchFBLitho(_ sender: UIButton) {
+    let imageURL = URL(string: "https://raw.githubusercontent.com/facebook/litho/master/docs/static/logo.png")!
+    let dataTask = URLSession.shared.dataTask(with: imageURL){ [weak self] (data, response, error) in
+      guard let strongSelf = self else { return }
+      guard let _ = data else {
+        strongSelf.showAlert(message: "Received no data in Images API")
+        return
+      }
+
+      if let errorUnwrapped = error {
+        strongSelf.showAlert(message: "Received error in Images API Error:\(errorUnwrapped.localizedDescription)")
+        return
+      }
+
+      // As sonar cannot detect print() in Logs
+      NSLog("Got Image")
+      strongSelf.showAlert(message: "Received Litho Image")
+    }
+    dataTask.resume()
+  }
+
+  func showAlert(message: String) {
+    let alertController = UIAlertController.init(title: "Flipper", message: message, preferredStyle: .alert);
+    let alertAction = UIAlertAction(title: "Okay", style: UIAlertActionStyle.default, handler: nil)
+    alertController.addAction(alertAction)
+    present(alertController, animated: true, completion: nil)
+  }
+}