Fixed Welcome screen from showing up on domain reload. (#28)

CHANGELOG.md

 
 #### Fixed
 
+* Fixed Welcome screen from showing up on domain reload.
 * Fixed Take Screenshot Action : Bad Filename + Added Tooltips
 * Fixed property name in NonNullCheck property drawer
 * Fixed Potential null in Discover Window

Editor/WelcomeScreen/WelcomeScreen.cs

         {
             if (showOnStartup && !GameplayIngredientsSettings.currentSettings.disableWelcomeScreenAutoStart)
                 EditorApplication.update += ShowAtStartup;
+
+            EditorApplication.quitting += EditorApplication_quitting;
+        }
+
+        const string kShowNextPreference = "GameplayIngredients.WelcomeScreen.ShowNextTime";
+
+        private static void EditorApplication_quitting()
+        {
+            EditorPrefs.SetBool(kShowNextPreference, true);
-            if (!Application.isPlaying)
+            if (!Application.isPlaying && EditorPrefs.GetBool(kShowNextPreference, true))
+                EditorPrefs.SetBool(kShowNextPreference, false);
             }
             EditorApplication.update -= ShowAtStartup;
         }