Recognize and display `init` property accessor

[vitek-karas]

C# now allows the init property accessor, in addition to get and set. In warning messages linker will show getter like Type.Property.get and setter like Type.Property.set. But it doesn't recognize init, it will see it as set instead.
Ideally for init accessor it would show Type.Property.init.
https://docs.microsoft.com/en-us/dotnet/csharp/language-reference/keywords/init