Provide a place in Worldbuilding to store reference Material.

When writing, we gather material, usually on the net, but often from other places. It would be good to be able to store this material within the project; I suggest in the World Building, so that Sudowrite can reference this particular material in providing words. For instance, I have a few articles on the road speed limits in New Zealand which I will use in a biography, but Sudowrite should be aware. This will not feature directly in the writing, but it may be appropriate to reference them. Same with drink age, driver licence eligibility during the years, etc.