#475 NullRefEx's as FullName returns null for inherited generics

[Harald M. Mueller]

NDoc assumes at many places that FullName is always
non-null. However, this is no longer true for generics
- I have attached an example which shows this behavior.
I'm not sure what to do with NDoc here - I fear this
requires big rethinking of how to represent types as
strings.

Regards
Harald M. Mueller

[Harald M. Mueller]

Example showing that FullName may sometimes return null for generics