Add link to upgrading clusters to ccr

[erzz99]

fixes #47218. I added a link to the upgrading clusters page in the overview page.

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[jasontedor]

Thanks for picking his up @erzz99 although I don't think this is straightforward enough. I think it's making the user work too hard to understand the requirements here. On the one hand, we link to the remote clusters documentation about the versioning, which shows a compatibility matrix that implies a broad range of compatibility, and then we link to the upgrade docs which itself isn't even direct enough about version compatibility. A user then has to piece this information together to understand the version compatibility. I think we should be simple and direct and not link off to two pages to try to answer this question, a user shouldn't have to work so hard.

[elasticmachine]

Pinging @elastic/es-distributed (:Distributed/CCR)

[elasticmachine]

Pinging @elastic/es-docs (>docs)

[jasontedor]

@erzz99 Are you interested in taking the PR to completion?

[erzz99]

Yes, I'll see it through. Sorry for the late reply. Best, Erskine.

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On Wed, Oct 9, 2019 at 3:39 PM Jason Tedor ***@***.***> wrote: @erzz99 <https://github.com/erzz99> Are you interested in taking the PR to completion? — You are receiving this because you were mentioned. Reply to this email directly, view it on GitHub <#47331?email_source=notifications&email_token=AMNDGQL2JMGEZRGHHRC2UZ3QNY6O3A5CNFSM4I4CHSG2YY3PNVWWK3TUL52HS4DFVREXG43VMVBW63LNMVXHJKTDN5WW2ZLOORPWSZGOEAZIPQY#issuecomment-540182467>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AMNDGQNJRJB63S6Z3GDLIZDQNY6O3ANCNFSM4I4CHSGQ> .

[jasontedor]

@erzz99 Just checking in to see if you can wrap this one up?

[ywelsch]

@jrodewig can you take this one over? Thank you

[jrodewig]

@ywelsch Will do. Thanks for routing.

[jrodewig]

@erzz99 I'm going to close this PR and attempt to address #47218 via a separate PR.