c# support

[bitwes]

Issues that need to be resolved to test c# from gdscript

• inst_to_dict does not work on c# scripts.
• GDScript cannot extend a C# script and vice versa. This complicates doubling/stubbing/spies.
• assert_is needs to support CSharpScript for 2nd parameter.
• Creating dynamic C# scripts

Issues that need to be resolved to test c# from c#

• Cannot extend GutTest in C#, so there will have to either be a wrapper for all of test.gd or a C# class with a test.gd instance that has been setup.
• The C# people will want to name their tests in PascalCase. This might be ok, since test prefix is configurable. But if you want to write tests in both C# and GDScript then we'll need a prefix for both. Also, I hate that C# likes PascalCase instead of camelCase for function names. Really hate it.
• The C# people might want an attribute for test methods/classes (i.e [TestClass], [TestMethod]). I'd rather go off the name because it's less typing and less loc, but it's probably a good practice to support this.

Questions

• What is it like to unit test Godot app with a c# framework? What is missing from those frameworks that GUT could contribute?