Added a SerializableScriptableObject to store asset GUID.

This replaces the previous serialization code. We can use the cached asset GUID to serialize assets to disk as well as load them through the Addressables system.

Author: Bronson Zgeb

UOP1_Project/Assets/ScriptableObjects/SaveSystem/SaveSystem.asset

@@ -14,6 +14,7 @@ MonoBehaviour:
   m_EditorClassIdentifier: 
   locationDatabase: {fileID: 11400000, guid: 9abcccc3f16b8c54e984de463d147899, type: 2}
   _loadLocation: {fileID: 11400000, guid: 00e3063edc5902e40832ea618644c597, type: 2}
+  _onSceneReady: {fileID: 11400000, guid: b729e40fc41dd8b4ea7aaf5c857f7186, type: 2}
   saveFilename: save.chop
   saveData:
-    _locationId: 47723aeb-1bae-48c7-a760-4d6339e4a68a
+    _locationId: 

UOP1_Project/Assets/ScriptableObjects/SceneData/Locations/LocationDatabase.asset

@@ -3,7 +3,7 @@
 /// <summary>
 /// Base class for ScriptableObjects that need a public description field.
 /// </summary>
-public class DescriptionBaseSO : ScriptableObject
+public class DescriptionBaseSO : SerializableScriptableObject
 {
 	[TextArea] public string description;
 }