Ability to persist Draw.io configuration between diagram instances

[shooftie]

This is possibly a duplicate of #46.

I use the desktop version of Draw.io and am able to create a custom configuration that applies each time I create a new document.

It would be great to be able to add this to embedded diagrams.

https://user-images.githubusercontent.com/2161844/161557673-d59a3393-6596-479e-ad44-68357cfc0293.mov