Add EfTest harness to project

Hi @hazzik. I have added a separate project to DelegateDecompiler that runs tests and builds documentation. You can find the output of the tests in the [GeneratedDocumentation](https://github.com/JonPSmith/DelegateDecompiler/tree/master/src/DelegateDecompiler.EfTests/GeneratedDocumentation) folder. It produces three files.
* [Summary](https://github.com/JonPSmith/DelegateDecompiler/blob/master/src/DelegateDecompiler.EfTests/GeneratedDocumentation/SummaryOfSupportedCommands.md)
* [Detail](https://github.com/JonPSmith/DelegateDecompiler/blob/master/src/DelegateDecompiler.EfTests/GeneratedDocumentation/DetailedListOfSupportedCommands.md)
* [Detail with SQL](https://github.com/JonPSmith/DelegateDecompiler/blob/master/src/DelegateDecompiler.EfTests/GeneratedDocumentation/DetailedListOfSupportedCommandsWithSQL.md)

There are two other important files:
* [How to add more tests](https://github.com/JonPSmith/DelegateDecompiler/blob/master/src/DelegateDecompiler.EfTests/GeneratedDocumentation/HowToAddMoreTests.md) documentation
* A [Header File](https://github.com/JonPSmith/DelegateDecompiler/blob/master/src/DelegateDecompiler.EfTests/GeneratedDocumentation/DocumentationHeaderText.md), which is added to the generated documentation. You may want to change that, as its your project.

Finally, if you accept the merge, then I would like to create some pages in the projects Wiki pointing to these pages.