Feature request DMD: fqn in message, if different types have the same name

[Frank Benoit]

If two types with the same name are defined, sometimes the messages of 
DMD are a bit strange:
  - cannot cast A to A
  - function foo( A ) does not match parameter A.
and so on. It would be helpful, if in case of the same name, the types 
would be given with full qualified names.