Updated Readme file to include link to microsoft#88

The issue thread microsoft#88 offers some great points on what makes a good pull request. However, it is buried under a lot of different issues and can be difficult to reach, especially for new contributors who might not know this discussion exists. As such, I felt it necessary to add a direct link to the thread under the "Contributing" section of the readme file.

README.md

@@ -97,6 +97,7 @@ You can read the code for more details.
 
 ## Contributing
 
+### Contributor License Agreement
 As mentioned above, this project welcomes contributions and suggestions.  Most contributions require you to agree to a
 Contributor License Agreement (CLA) declaring that you have the right to, and actually do, grant us
 the rights to use your contribution. For details, visit https://cla.microsoft.com.
@@ -109,6 +110,9 @@ This project has adopted the [Microsoft Open Source Code of Conduct](https://ope
 For more information see the [Code of Conduct FAQ](https://opensource.microsoft.com/codeofconduct/faq/) or
 contact [[email protected]](mailto:[email protected]) with any additional questions or comments.
 
+### What Makes a Good Pull Request for WinFile?
+If you are interested in contributing and/or suggesting changes to the actual application, you might find it helpful to [read this post first](https://github.com/Microsoft/winfile/issues/88).
+
 ## License
 
 Copyright (c) Microsoft Corporation. All rights reserved.