Adding NuGet.exe restore to build.cmd

Enables binaries to be removed from source control

.gitignore

@@ -16,3 +16,4 @@ target
 StyleCop.Cache
 node_modules
 *.snk
+.nuget/NuGet.exe

build.cmd

@@ -1,8 +1,11 @@
 @echo off
 cd %~dp0
 
+IF EXIST .nuget\NuGet.exe goto part2
+echo Downloading latest version of NuGet.exe...
+@powershell -NoProfile -ExecutionPolicy unrestricted -Command "((new-object net.webclient).DownloadFile('https://nuget.org/nuget.exe', '.nuget\NuGet.exe'))"
+
+:part2
 set EnableNuGetPackageRestore=true
-
 .nuget\NuGet.exe install Sake -version 0.2 -o packages
-
 packages\Sake.0.2\tools\Sake.exe -I build -f Sakefile.shade %*