Implement Redirects in Gitbook for legacy developers.gnosischain.com pages

[plato-gno]

We may be able to specify the basepath as the new docs.gnosischain.com site, and redirect developers.gnosischain.com to the new site

https://github.com/getgauge-contrib/gitbook-plugin-bulk-redirect/blob/master/README.md#redirects-in-redirectsjson

[alebanzas]

Old website still hosts Optimism on GC information. We need to transfer those first, then generate HTTP permanent redirects and deprecate gitbook.

[alebanzas]

Dependency: #190

[plato-gno]

I was actually thinking of doing the migration 1-by-1, and defining custom 302 rules for each page that we migrate.

I was trying to find an old page from the Gitbook yesterday (regarding ETHDenver 2019). Unfortunately the page got redirected, even though the content was not migrated.

https://developers.gnosischain.com/about-gc/use-cases/cryptocurrency-for-events-and-conferences/ethdenver-2020-xdai-and-burner-wallet-recap

I would actually recommend we restore some of the old pages, and have an incremental migration

• Banner on top of developer.gnosischain, indicating that docs are outdated and to visit new docs site
• nginx box that does URL-by-URL 302s (we can keep the k8s nginx configmap in repo, so that contributors can add URLs)
• Set up 302s only when content has been migrated (or we are very sure that its not needed)

We can probably use the lull after the Merge to re-pick up on the docs effort, hopefully with more contributors this time from the community. There's a lot of resources in the old docs (news articles, etc), and it'd be a great way for new contributors to learn more about the chain's history.

Any thoughts? @CVJoint @jbradach

[alebanzas]

Added Optimism in #190
At this point, I would fully deprecate developers.gnosischain.com with 301 redirects to the docs. And spin off a task for migrating historical data under Gnosis Chain History sub-section in the about.

[alebanzas]

URL Planning tab redirects developers

[alebanzas]

Dependencies:

• Add steps for how to set up and add a new bridge validator #72
• History #327