The following commits address: StackExchange#1659

  Where basically after manual failover the replicas endpoint list is
not refreshed.

  ServerSelectionStrategy.cs

  Updated:
   - SetClusterConfiguration to call new method UpdateNodeRelations with
the configuration
  Added:
   - UpdateNodeRelations to have the same update logic that it was
before in SetClusterConfiguration so it could be used in
ConnectionMultiplexer

   ConnectionMultiplexer.cs
   Updated:
   - GetEndpointsFromClusterNodes, to call UpdateNodeRelations and
refresh the configuration before returning the endpoints list