Draft for IL decompilation

[jl0pd]

This PR add new type CompiledLibrary which contains compiled library bytes, producing compilation and methods to assert that compilation was right.

Example usage:

string program = $"""
    module Math =
        fn test of x =
            x + 2
    end
    """;

CompileLibrary library = CompileLibrary(program);

library.AssertIL("Math.test", """
    {
        ldarg.0
        ldc.i4.2
        ret
    }
    """)

library.Execute("Math.test", b => {
    b.WithArguments(7);
    b.Return(result => {
         Assert.Equal(9, result);
    });
});

[jl0pd]

This thing has bad debugging experience. It just tells that string didn't match, but doesn't say where