Backport to branch(3.12) : Add data import enums

data-loader/core/src/main/java/com/scalar/db/dataloader/core/dataimport/ImportMode.java

@@ -0,0 +1,8 @@
+package com.scalar.db.dataloader.core.dataimport;
+
+/** Represents the way to be imported data is handled */
+public enum ImportMode {
+  INSERT,
+  UPDATE,
+  UPSERT
+}

data-loader/core/src/main/java/com/scalar/db/dataloader/core/dataimport/controlfile/ControlFileValidationLevel.java

@@ -0,0 +1,11 @@
+package com.scalar.db.dataloader.core.dataimport.controlfile;
+
+/** Control file validation level */
+public enum ControlFileValidationLevel {
+  /* All columns need to be mapped */
+  FULL,
+  /* All partition key and clustering key columns need to be mapped */
+  KEYS,
+  /* Only validate the columns that are mapped */
+  MAPPED
+}