Docs:Redirects

New redirects: How to handle each case?

1. redirect-only inside the same collection (aka, permanaent alias).
   • [thoughts]
2. redirect-only to a different collection.
   • [thoughts]
3. deprecation with no redirect.
   • needs no special logic, since it is already handled by the regular docs build (ansible-test sanity ensures that runtime.yml deprecations agree with in-module deprecations)
4. deprecation and redirect inside the same collection.
   • [thoughts]
5. deprecation and redirect to a different collection.
   • [thoughts]

Existing redirects