'Recent' panel in 'Create new node' popup is never cleared.

[AndHalfAFish]

Godot version:
3.2beta4

OS/device including version:
Windows 10

Issue description:
'Recent' panel in 'Create new node' popup is never cleared, which makes it useless.

Steps to reproduce:
In the scene tab > add new node > 'create new node' popup > add a node
Repeat a couple of times.
When Godot is restarted, all those nodes are still present in 'recent'. They should have been cleared.

Minimal reproduction project:

[akien-mga]

Why does it make it useless?

The point is that it lists what nodes you last use, regardless of the session.
All software does that with their "Recent files" features.

[AndHalfAFish]

If it's never cleared, it just becomes identical to the main list.
The behavior I expect is : no clearing during 1 session , clearing after I restart Godot. I think this is what the behaviour used to be in previous versions of Godot.

[akien-mga]

It should be ordered by reverse chronological order (last used nodes come first), so it's not the same as the main list.

But it should likely be limited to ~10-15 entries or so, removing the older ones as new ones come in.

[AndHalfAFish]

Yes. That would be an option too.
That, or just a simple clear.

[Calinou]

Limiting the Recent menu to about 10 entries is probably a better idea indeed.

[tektrip-biggles]

Another issue with this never being cleared (whether manually or automatically) is that if you move / rename files with custom classes, you can end up with broken links in the "Recent" panel, along with a couple of error messages every time you open the "create new node" dialog:

Attempt to open script 'res://MyOldScriptName.gd' resulted in error 'File not found'.
  editor/create_dialog.cpp:266 - Condition "inherits.is_empty()" is true.