Custom stage background

Feature request. Adding a custom scene background. Instead of the tile grid.

Controls could be included in "Product Options" (apply to all child product layers) or per layer in"Product Builder" (applies only to specific layer).

For my case. I am using a dynamic width for the product designer interface and constrain the editing area to the product bounding box. 

So being able to change background in .fpd-main-wrapper would enhance the stage and make it more attractive.

Example of scene: 

Optionally, a bonus could also be to have controls for; position, repeat and size property e.g "cover", "contain" etc.