Adding island scene and default

ProjectSettings/EditorBuildSettings.asset

   serializedVersion: 2
   m_Scenes:
   - enabled: 1
-    path: Assets/Scenes/SampleScene.unity
-    guid: d1c3109bdb54ad54c8a2b2838528e640
+    path: Assets/IslandScene/Scene_Island.unity
+    guid: fbf0e7428e89fd0449107fa9b931e311
   m_configObjects: {}