structuredLicense missing when content fetched from AGO

[mjuniper]

If getContent is called on ccfa083a64f14e07ab28ef6db04483ff, structuredLicense will be present on the results. However, if getContent is called on f584b3bf5e324524a25fbfe7d1b714f4, structuredLicense will not be present.

This is because the former is public and thus is fetched from the Hub API which augments the results with structuredLicense while the latter is not public and thus is fetched from the AGO API.

I think we should move whatever logic constructs the structuredLicense out of the Hub API and into Hub.js so that it can be applied in both cases.

Additionally, the logic we are currently using to construct the structuredLicense needs to be updated to conform to the requirements enumerated in this story.

Related: #439

[thomas-hervey]

@tomwayson how high of a priority is this? I am alright with @sonofflynn89 taking on this issue so long as we're clear if/what needs to be changed in the Hub API.