add addKeyValueAnnotationsAsText flag

Author: LittleLittleCloud

src/Microsoft.ML.AutoML/CodeGen/map_value_to_key_search_space.json

@@ -9,6 +9,11 @@
     {
       "name": "InputColumnName",
       "type": "string"
+    },
+    {
+      "name": "AddKeyValueAnnotationsAsText",
+      "type": "boolean",
+      "default": false
     }
   ]
 }

src/Microsoft.ML.AutoML/CodeGen/search-space-schema.json

@@ -177,7 +177,8 @@
         "Sentence2ColumnName",
         "BatchSize",
         "MaxEpochs",
-        "Architecture"
+        "Architecture",
+        "AddKeyValueAnnotationsAsText"
       ]
     },
     "option_type": {

src/Microsoft.ML.AutoML/SweepableEstimator/Estimators/MapValueToKey.cs

@@ -8,7 +8,7 @@ internal partial class MapValueToKey
     {
         public override IEstimator<ITransformer> BuildFromOption(MLContext context, MapValueToKeyOption param)
         {
-            return context.Transforms.Conversion.MapValueToKey(param.OutputColumnName, param.InputColumnName);
+            return context.Transforms.Conversion.MapValueToKey(param.OutputColumnName, param.InputColumnName, addKeyValueAnnotationsAsText: param.AddKeyValueAnnotationsAsText);
         }
     }