Consider adding archived license links

[stepps00]

We should consider adding a new property to each source that contains an archived link to each source license. Sometimes source license links no longer work; adding an archived link would let WOF maintain original license text in most source json files.

[nvkelso]

You mean to Internet Archive? Or saving the raw text of the license text into our JSON? Or adding the raw original license text as a sidecar file into this repo next to the JSON for the source (like we do for remarks files in the data repos)?

[stepps00]

Internet Archive, but I'm not opposed to storing raw text in the repo (sidecar files or other), either.