Ability to specify the background image per file

[jamesfoster-excelpoint]

I'd like to be able to set the background images for a file or folder.

For example, when I open Product.cs I'd like to see an image of a warehouse, but when I open Shipment.cs I'd like to see an image of cargo containers or lorries.

This could be done via a comment in the file

// background-image: products.png

Or, via a config file. This could also be useful if you want a background image for an entire folder. maybe a dotfile like .background-image

background-image=products.png

Or something a bit more structured

images:
  - path: source/Model/Products/*
    image: bg/products.png
  - path: source/Api/Shipment.cs
    image: bg/shipment.png
  - path: docs/*
    image: bg/docs.png