D1 & D2 alpha's for Win64

[Moritz Maxeiner]

To get this working with Visual Studio 2012 on Windows 8 one can 
use this (or a similar) sc.ini (Then it works perfectly fine, 
thank you Walter!):

[Version]
version=7.51 Build 020

[Environment]
LIB=C:\Program Files (x86)\Windows 
Kits\8.0\Lib\win8\um\x64;"%@P%\..\lib";\dm\lib
DFLAGS="-I%@P%\..\..\src\phobos" 
"-I%@P%\..\..\src\druntime\import"
VCINSTALLDIR=C:\Program Files (x86)\Microsoft Visual Studio 
11.0\VC\
WindowsSdkDir=C:\Program Files (x86)\Microsoft SDKs\Windows\v7.0A\
LINKCMD=c:\dm\bin\link.exe
LINKCMD64=%VCINSTALLDIR%bin\amd64\link.exe


One more thing: It's been asked before in this thread, but I 
haven't seen a reply by Walter yet: Is it viable to add the 
option of using the VC linker for 32bit, e.g. as something like 
"-linkvc". And I don't mean to remove optlink or anything like 
that, just as an option.