Merge pull request #1 from SciSharp/master

Merge from master repo

Author: NiklasGustafsson

src/TensorFlowNET.Keras/Preprocessings/Preprocessing.cs

@@ -10,6 +10,10 @@ public partial class Preprocessing
         public Sequence sequence => new Sequence();
         public DatasetUtils dataset_utils => new DatasetUtils();
 
+        public TextApi text => _text;
+
+        private static TextApi _text = new TextApi();
+
         public TextVectorization TextVectorization(Func<Tensor, Tensor> standardize = null,
             string split = "whitespace",
             int max_tokens = -1,