Fixed execution order issue

+Fixed issue with execution order when placing new element to track, that required Unity to be restarted
Interesting note: OnEnable() of RewindAbstract.cs was actually called before Awake() of RewindManager.cs which is apparently not a bug: https://issuetracker.unity3d.com/issues/awake-function-called-after-onenable

Author: SitronX

Assets/TimeRewinder/TimeRewinderImplementation/Scripts/RewindAbstract.cs

@@ -317,19 +317,13 @@ private void OnTrackingChange(bool val)
     }
     protected void OnEnable()
     {
-        if(rewindManager != null)
-        {
-            RewindManager.RewindTimeCall += Rewind;
-            RewindManager.TrackingStateCall += OnTrackingChange;
-        }
+        RewindManager.RewindTimeCall += Rewind;
+        RewindManager.TrackingStateCall += OnTrackingChange;        
     }
     protected void OnDisable()
     {
-        if(rewindManager != null)
-        {
-            RewindManager.RewindTimeCall -= Rewind;
-            RewindManager.TrackingStateCall -= OnTrackingChange;
-        }       
+        RewindManager.RewindTimeCall -= Rewind;
+        RewindManager.TrackingStateCall -= OnTrackingChange;            
     }
 
     /// <summary>

Assets/TimeRewinder/TimeRewinderImplementation/Scripts/RewindManager.cs

@@ -37,10 +37,6 @@ private void OnEnable()
     }
     private void Awake()
     {
-        RewindTimeCall = null;
-        TrackingStateCall = null;
-        RestoreBuffers = null;
-
         RewindManager[] managers= FindObjectsOfType<RewindManager>();
 
         if (managers.Length>1)                                               //Check if each scene contains only one script with RewindManager