use grpc to replace http APIs for batch volume id lookup and batch delete

1. remove batch volume id lookup http API /vol/lookup
2. remove batch delete http API /delete

weed/server/master_grpc_server_lookup.go

@@ -0,0 +1,28 @@
+package weed_server
+
+import (
+	"github.com/chrislusf/seaweedfs/weed/pb/master_pb"
+	"context"
+)
+
+func (ms *MasterServer) LookupVolume(ctx context.Context, req *master_pb.LookupVolumeRequest) (*master_pb.LookupVolumeResponse, error) {
+	resp := &master_pb.LookupVolumeResponse{}
+	volumeLocations := ms.lookupVolumeId(req.VolumeIds, req.Collection)
+
+	for _, result := range volumeLocations {
+		var locations []*master_pb.Location
+		for _, loc := range result.Locations {
+			locations = append(locations, &master_pb.Location{
+				Url:       loc.Url,
+				PublicUrl: loc.PublicUrl,
+			})
+		}
+		resp.VolumeIdLocations = append(resp.VolumeIdLocations, &master_pb.LookupVolumeResponse_VolumeIdLocation{
+			VolumeId:  result.VolumeId,
+			Locations: locations,
+			Error:     result.Error,
+		})
+	}
+
+	return resp, nil
+}