Specify redist version to 2.3.1 for now

Author: Banyc

README.md

@@ -50,10 +50,10 @@ PM> Install-Package TensorFlow.Keras
 
 ### Install tensorflow binary
 ### For CPU version
-PM> Install-Package SciSharp.TensorFlow.Redist
+PM> Install-Package SciSharp.TensorFlow.Redist -Version 2.3.1
 
 ### For GPU version (CUDA and cuDNN are required)
-PM> Install-Package SciSharp.TensorFlow.Redist-Windows-GPU
+PM> Install-Package SciSharp.TensorFlow.Redist-Windows-GPU -Version 2.3.1
 ```
 
 Import TF.NET and Keras API in your project.