Notification scanner slept max time when tablets changed
I noticed this while running the stress test.  The test started the Fluo app and then later added splits to the table.  Fluo eventually noticed these new splits and when it did scanned 0 tablets and then slept for 5 mins (which is the max time to sleep between tablet scans).   This case could be handled in a more responsive way.

```
14:02:52.596 [Fluo-0007-001-Fluo worker partition manager] DEBUG o.a.f.c.w.f.hash.ParitionManager - Updated finder partition info : workers:2  groups:1  groupSize:2  groupId:0  idInGroup:1  #tablets:10
14:02:52.635 [PartitionNotificationFinder ScanTask] DEBUG o.a.f.c.worker.finder.hash.ScanTask - Scanned 0 of 1 tablets. Notifications added: 0 seen: 0 queued: 0
14:07:52.786 [PartitionNotificationFinder ScanTask] DEBUG o.a.f.c.worker.finder.hash.ScanTask - Scanned 10 of 10 tablets. Notifications added: 331 seen: 331 queued: 38
```
diff --git a/modules/core/src/main/java/org/apache/fluo/core/worker/finder/hash/ScanTask.java b/modules/core/src/main/java/org/apache/fluo/core/worker/finder/hash/ScanTask.java
index 35f3215f..00726a8d 100644
--- a/modules/core/src/main/java/org/apache/fluo/core/worker/finder/hash/ScanTask.java
+++ b/modules/core/src/main/java/org/apache/fluo/core/worker/finder/hash/ScanTask.java
@@ -76,7 +76,6 @@ public class ScanTask implements Runnable {
   @Override
   public void run() {
 
-
     List<TableRange> ranges = new ArrayList<>();
     Set<TableRange> rangeSet = new HashSet<>();
 
@@ -135,7 +134,12 @@ public class ScanTask implements Runnable {
           // nothing to do
         }
 
-        long sleepTime = Math.max(minSleepTime, minRetryTime - System.currentTimeMillis());
+        long sleepTime;
+        if (!partition.equals(partitionManager.getPartitionInfo())) {
+          sleepTime = minSleepTime;
+        } else {
+          sleepTime = Math.max(minSleepTime, minRetryTime - System.currentTimeMillis());
+        }
 
         qSize = proccessor.size();
 
['modules/core/src/main/java/org/apache/fluo/core/worker/finder/hash/ScanTask.java']