Removing ddoc and unittest

[Christopher Wright]

Janderson wrote:
> *sigh* This is smart and all.  However this is the sort of thing that 
> puts me off unit tests that are not part of the language (or their own 
> language).  It feels like a big hack to me.
> 
> -Joel

I sympathize. D needs better runtime reflection with user-defined 
metadata for a reasonable solution.

Unit testing is sufficiently important for me that I'm willing to deal 
with odd syntax.