Revert "removed force bootstrap as its nolonger required"

This reverts commit bc48a6aefb.

src/main/java/net/openhft/chronicle/map/UdpReplicator.java

@@ -91,6 +91,11 @@ class UdpReplicator extends AbstractChannelReplicator implements Replica.Modific
     }
 
 
+    @Override
+    public void forceBootstrap() {
+        modificationIterator = replica.acquireModificationIterator(
+                ChronicleMapBuilder.UDP_REPLICATION_MODIFICATION_ITERATOR_ID, this);
+    }
 
     /**
      * binds to the server socket and process data This method will block until interrupted