Merge branch 'dewet-geo-dr-limits' into 'master'

Point DR limitations to what is replicated

Edits this https://gitlab.com/help/gitlab-geo/README.md#can-i-use-geo-in-a-disaster-recovery-situation

I see **Current limitations** as limitations for using it as a network speed tool. Limitations for disaster recovery is better laid out in the **"What data is replicated"** section that I am linking to now.

See merge request !831

doc/gitlab-geo/README.md

@@ -88,7 +88,8 @@ See more details in the [Configure GitLab](configuration.md) step.
 
 ### Can I use Geo in a disaster recovery situation?
 
-There are limitations to what we replicate (see Current limitations).
+There are limitations to what we replicate (see
+[What data is replicated to a secondary node?](#what-data-is-replicated-to-a-secondary-node)).
 In an extreme data-loss situation you can make a secondary Geo into your
 primary, but this is not officially supported yet.