replicate: use creation time for local incremental file sink

related to https://github.com/chrislusf/seaweedfs/pull/1762

weed/replication/sink/localsink/local_incremental_sink.go

@@ -0,0 +1,17 @@
+package localsink
+
+import (
+	"github.com/chrislusf/seaweedfs/weed/replication/sink"
+)
+
+type LocalIncSink struct {
+	LocalSink
+}
+
+func (localincsink *LocalIncSink) GetName() string {
+	return "local_incremental"
+}
+
+func init() {
+	sink.Sinks = append(sink.Sinks, &LocalIncSink{})
+}