Possibility to change background image

[BrightShadow]

• I propose to add possibility to change background image.
  • if new image is smaller than objects area, the background image will get white borders
  • if background image is bigger than previous one the content of page will be aligned to left upper corner
  • User should be able to set new background image positioning if there is a content and new image has smaller height or width then previous one - a dialog should be shown with something simlar to this below: