Gather design recommendations to allow:

• Consumers of section recommendations APIs learn how the recommendations are generated, and report issues on the recommendation pipeline (category network relations, in this case)
• http://gapfinder.wmflabs.org/en.wikipedia.org/v1/section/article/Barack_Obama
• http://gapfinder.wmflabs.org/en.wikipedia.org/v1/section/category/Presidents

• Users of the section recommendation gadget can see the reason for recommendations (category path) and report issues.