Updating the CopyColumnsEstimator and Transform to use common code (#706) (#1141)

* Updating the CopyColumnsEstimator and Transform to use common code
  (#706)
This builds on the Estimator conversion for the CopyColumnsTransform.
This change is mainly refactoring as common code has moved to base level classes.

This change is the following:
       - CopyColumnTransform now derives from OneToOneTransformerBase
       - CopyColumnEstimator now derives from TrivialEstimator
       - CopyColumnTransform::Mapper now derives from MapperBase
       - Removed code that was no longer needed due to these changes

*  - Moved CopyColumnsTransform into Microsoft.ML.Transforms namespace,
 updated namespace usage and entrypoints due to this change.
 - Save now uses the SaveColumns from the base class
 - Other various changes based upon feedback.

Author: singlis

src/Microsoft.ML.Data/EntryPoints/SchemaManipulation.cs

@@ -2,12 +2,10 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for more information.
 
-using System.Collections.Generic;
-using System.Linq;
 using Microsoft.ML.Runtime;
-using Microsoft.ML.Runtime.CommandLine;
 using Microsoft.ML.Runtime.Data;
 using Microsoft.ML.Runtime.EntryPoints;
+using Microsoft.ML.Transforms;
 
 [assembly: LoadableClass(typeof(void), typeof(SchemaManipulation), null, typeof(SignatureEntryPointModule), "SchemaManipulation")]
 

src/Microsoft.ML.Data/EntryPoints/ScoreColumnSelector.cs

@@ -2,13 +2,12 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for more information.
 
+using Microsoft.ML.Runtime.CommandLine;
+using Microsoft.ML.Runtime.Data;
+using Microsoft.ML.Transforms;
 using System;
 using System.Collections.Generic;
 using System.Linq;
-using Microsoft.ML.Runtime;
-using Microsoft.ML.Runtime.CommandLine;
-using Microsoft.ML.Runtime.Data;
-using Microsoft.ML.Runtime.EntryPoints;
 
 namespace Microsoft.ML.Runtime.EntryPoints
 {

src/Microsoft.ML.Data/Evaluators/MulticlassClassifierEvaluator.cs

@@ -8,6 +8,7 @@
 using Microsoft.ML.Runtime.EntryPoints;
 using Microsoft.ML.Runtime.Internal.Utilities;
 using Microsoft.ML.Runtime.Model;
+using Microsoft.ML.Transforms;
 using System;
 using System.Collections.Generic;
 using System.Linq;

src/Microsoft.ML.Data/StaticPipe/Reconciler.cs

@@ -2,11 +2,11 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for more information.
 
-using System;
-using System.Collections.Generic;
 using Microsoft.ML.Core.Data;
 using Microsoft.ML.Runtime;
-using Microsoft.ML.Runtime.Data;
+using Microsoft.ML.Transforms;
+using System;
+using System.Collections.Generic;
 
 namespace Microsoft.ML.StaticPipe.Runtime
 {

src/Microsoft.ML.Data/StaticPipe/StaticPipeUtils.cs

@@ -9,6 +9,7 @@
 using Microsoft.ML.Core.Data;
 using Microsoft.ML.Runtime;
 using Microsoft.ML.Runtime.Data;
+using Microsoft.ML.Transforms;
 
 namespace Microsoft.ML.StaticPipe.Runtime
 {

src/Microsoft.ML.Data/StaticPipe/TrainerEstimatorReconciler.cs

@@ -2,12 +2,13 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for more information.
 
-using System.Collections.Generic;
-using System.Linq;
 using Microsoft.ML.Core.Data;
 using Microsoft.ML.Runtime;
 using Microsoft.ML.Runtime.Data;
 using Microsoft.ML.Runtime.Internal.Utilities;
+using Microsoft.ML.Transforms;
+using System.Collections.Generic;
+using System.Linq;
 
 namespace Microsoft.ML.StaticPipe.Runtime
 {