Do read request to local + originating replicas only for read-after-write case

[zzmao]

With pull request #827 , we are able to reorder replicas in the order of local, originating and then other dc replicas.

One more enhancement can be done based on this is do read request to 'local + originating' only in read-after-write case.

We should have a configuration to turn on/off this.