Docs: move from grafana-plugin-sdk-go/data

[kylebrandt]

can we move this to /docs/contract/ folder so that it will become easier to add more docs later?

Will do, also I have not done GH pages in ages - does this need to go anywhere special?

[yesoreyeram]

docs is fine for gh-pages but to make it future proof i suggested that. I will make a follow-up PR to make the gh-pages work properly.

[yesoreyeram]

It is now live in https://grafana.github.io/dataplane/contract/