refactor(SQLStages): Added String() func

SQL/SQLStages.go

@@ -1,5 +1,7 @@
 package SQL
 
+import "fmt"
+
 type SQLStage int64
 
 const (
@@ -7,3 +9,16 @@ const(
 	SQLStage_Upload    = 2
 	SQLStage_DeleteTmp = 3
 )
+
+func (e SQLStage) String() string {
+	switch e {
+	case SQLStage_Compress:
+		return "COMPRESS"
+	case SQLStage_Upload:
+		return "UPLOAD"
+	case SQLStage_DeleteTmp:
+		return "DELETE TMP"
+	default:
+		return fmt.Sprintf("%d", e)
+	}
+}