Moved 'How-tos/D for Win32' to wiki

This is a test pull.  I think it would be best to move the How-tos to the wiki.  This is the first, and if it is accepted, I'll move the other How-tos.

Motivation:
*  Elicit more community involvement in updating the documentation.  
*  Updating the wiki is easier than submitting pull requests.
*  DLang.org changes are not immediate, the wiki is.  Instant gratification is good.
*  Having these How-tos on dlang.org implies that the core D effort is maintaining it.  I doubt this is the case, and I think the community as a whole could do a better job anyway.  In fact, I'm skeptical the example in this how-to even still compiles.

If this pull is accepted, I'll move the other how-tos to here: http://wiki.dlang.org/Tutorials

The new location of this specific how-to is here: http://wiki.dlang.org/D_for_Win32