very crude fix for the translate key read-only bug

This PR forces the non-coordinator nodes to reset their translation
sync (and therefore their own cosideration of read-only partitions)
any time they receive a `ClusterStatus` message. So basically, as the
cluster grows during the startup process, each node will reset their
translation sync.

This is NOT a good solution log term, but it should address the
immediate problem.

Things to note:
- the coordinator sync isn't getting reset, but that's ok, because the
immediate problem is a partition marked as read-only when it shouldn't
be; i.e. it's ok to have the inverse (a partition not marked as
read-only when it should be) because that partition won't receive
requests anyway.
- the last node to start is already correct and doesn't really need to
reset its sync.
- there are many other scenarios not covered by this fix.

Based on this theory:

```
i have another theory that i’m going to try to test.
this one would only apply in the case where a multi-node cluster is restarted with an existing, keyed index.
- start node0: it thinks it’s responsible for all partitions (nothing is read-only)
- start node1: it thinks it’s responsible for ~1/2 of the partitions and marks the other 1/2 as read-only
- start node2: it thinks it’s responsible for ~1/3 of the partitions and marks the other 2/3 as read-only
now if node0 is the coordinator receiving all translation requests, that still might not explain what’s happening, because in that case it would just do all the translating. i think. but either way, i should make sure that scenario is not happening, but i think it may be.

actually, that might explain it, because what would happen when the coordinator received a translation request, is that it would handle the 1/3 that it owned (now that the cluster is 3 nodes), and it would send the other 2/3 out to the other 2 nodes. but where it sent the requests wouldn’t line up with what the nodes thought they were responsible for based on the restart order
in this example, node 1 would receive requests for the wrong partitions
```

server.go

@@ -725,6 +725,11 @@ func (s *Server) receiveMessage(m Message) error {
 		if err != nil {
 			return err
 		}
+		if s.syncer.Cluster != nil {
+			if err := s.syncer.ResetTranslationSync(); err != nil {
+				return err
+			}
+		}
 	case *ResizeInstruction:
 		err := s.cluster.followResizeInstruction(obj)
 		if err != nil {