CCBC-202: Don't try to switch to backup nodes when timeout is reached

Change-Id: I8333218058229a3988c4c69eafff959e06ec9400
Reviewed-on: http://review.couchbase.org/25711
Reviewed-by: Trond Norbye <trond.norbye@gmail.com>
Reviewed-by: Sergey Avseyev <sergey.avseyev@gmail.com>
Tested-by: Sergey Avseyev <sergey.avseyev@gmail.com>