Primitive, Pointer, Array and Method types are anonymous now

Primitive, Pointer, Array and Method types are anonymous now
- There's a new type_dbg_info* that allows you to attach debug names to types
- get_type_name and get_type_ident are now more. The new ir_print_type
  and the usual ir_printf("%+F", type) help in most usage cases.
  But you should be aware that names are not guaranteed to be unique anymore
  (or positively said: You don't have no trouble anymore building unique names
   in code that creates types)
- No need to specify mode for new pointer types anymore (you can still do it
  with set_type_mode)

[r26909]