Add ParrelSync and netcode

Assets/ParrelSync/Editor/UpdateChecker.cs

@@ -0,0 +1,60 @@
+using System;
+using UnityEditor;
+using UnityEngine;
+namespace ParrelSync.Update
+{
+    /// <summary>
+    /// A simple update checker
+    /// </summary>
+    public class UpdateChecker
+    {
+        //const string LocalVersionFilePath = "Assets/ParrelSync/VERSION.txt";
+        public const string LocalVersion = "1.5.3";
+        [MenuItem("ParrelSync/Check for update", priority = 20)]
+        static void CheckForUpdate()
+        {
+            using (System.Net.WebClient client = new System.Net.WebClient())
+            {
+                try
+                {
+                    //This won't work with UPM packages
+                    //string localVersionText = AssetDatabase.LoadAssetAtPath<TextAsset>(LocalVersionFilePath).text;
+
+                    string localVersionText = LocalVersion;
+                    Debug.Log("Local version text : " + LocalVersion);
+
+                    string latesteVersionText = client.DownloadString(ExternalLinks.RemoteVersionURL);
+                    Debug.Log("latest version text got: " + latesteVersionText);
+                    string messageBody = "Current Version: " + localVersionText +"\n"
+                                         +"Latest Version: " + latesteVersionText + "\n";
+                    var latestVersion = new Version(latesteVersionText);
+                    var localVersion = new Version(localVersionText);
+
+                    if (latestVersion > localVersion)
+                    {
+                        Debug.Log("There's a newer version");
+                        messageBody += "There's a newer version available";
+                        if(EditorUtility.DisplayDialog("Check for update.", messageBody, "Get latest release", "Close"))
+                        {
+                            Application.OpenURL(ExternalLinks.Releases);
+                        }
+                    }
+                    else
+                    {
+                        Debug.Log("Current version is up-to-date.");
+                        messageBody += "Current version is up-to-date.";
+                        EditorUtility.DisplayDialog("Check for update.", messageBody,"OK");
+                    }
+                    
+                }
+                catch (Exception exp)
+                {
+                    Debug.LogError("Error with checking update. Exception: " + exp);
+                    EditorUtility.DisplayDialog("Update Error","Error with checking update. \nSee console for more details.",
+                     "OK"
+                    );
+                }
+            }
+        }
+    }
+}