v2.6.2

A new PlayableGraph search function has been added #25
Thanks to @hankangwen

Known issues (won't fix) :

• In Unity 2019.4, after closing the search popup, it will cause a certain control to obtain the input focus (such as the search box in the Console)
• In Unity 2020.3, The following error will be printed after the OnBeforeAssemblyReload event is raised (does not affect functionality):

  NullReferenceException: Object reference not set to an instance of an object
  UnityEditor.EditorWindow.Close () (at <25578071f6e44201aac745680e5c8dfc>:0)
  UnityEditor.PopupWindow.CloseWindow () (at <25578071f6e44201aac745680e5c8dfc>:0)
  UnityEditor.AssemblyReloadEvents.OnBeforeAssemblyReload () (at <25578071f6e44201aac745680e5c8dfc>:0)