Add Win8.1 to MakeRelease.

Author: jlaanstra

MakeRelease.ps1

@@ -1,6 +1,6 @@
 Param([string]$version = $null)
 
-$Archs = {"Portable-Net45+WinRT45+WP8", "Net45", "WP8", "WinRT45", "Mono", "Monoandroid", "Monotouch", "Monomac"}
+$Archs = {"Portable-Net45+WinRT45+WP8", "Net45", "WP8", "WinRT45", "WinRT451", "Mono", "Monoandroid", "Monotouch", "Monomac"}
 $Projects = {
     "ReactiveUI", "ReactiveUI.Testing", "ReactiveUI.Platforms", "ReactiveUI.Blend", 
     "ReactiveUI.Mobile", "RxUIViewModelGenerator", "ReactiveUI.Events"