On Reach API docs add links to support, website and github repo

[aoifespenge]

At the moment if a user wants more info and has a question, there is no-where for them to go to do this. They may want to ask a question, log an issue, read github docs, read about the purpose of Reach (website), reach about its creators (e.g. Medium). I suggest it simply needs to links to thigns like a contact form, the website, github repo and our Medium channel