Named unittests

[Panke via Digitalmars-d]

>
> I've implemented this in a library and I'm sure others have as 
> well. Are you sure, you want a language solution?

Basic principle:

---
unittest {

     testCase("a testcase",
     {
         // actual test code here
     });
}
---

Testcase registers the structure and the runtime just runs the 
unittest as is does today and than calls all closures registered 
during the unittest. Makes this fully backward compatible.